Input device, display device, and electronic device

ABSTRACT

A noise immunity of a detected capacitance is prevented or inhibited from lowering on a driving electrode different in width from the other driving electrodes, provided in an input device. A touch panel serving as an input device has a plurality of driving electrodes extending in an X-axis direction and arranged in a Y-axis direction intersecting with the X-axis direction, and a driving electrode arranged outside one side of an arrangement of the driving electrodes and extending in the X-axis direction. Further, the touch panel TP 1  has a plurality of detecting electrodes extending in the Y-axis direction and arranged in the X-axis direction. The width of the driving electrode is smaller than the widths of the driving electrodes and the detecting electrode includes an expanding portion for expanding the area of the detecting electrode on the side opposite to the plurality of driving electrodes via the driving electrode.

CROSS REFERENCES TO RELATED APPLICATIONS

The present application claims priority to Japanese Priority PatentApplication JP 2013-021912 filed in the Japan Patent Office on Feb. 7,2013, the entire content of which is hereby incorporated by reference.

BACKGROUND

The present invention relates to an input device, a display device, andelectronic device, and in particular to an input device of a capacitancetype, and a display device and electronic device which are provided withsuch an input device.

In recent years, technique of attaching an input device which is called“touch panel” or “touch sensor” to a display surface side of a displaydevice, and when an input action has been performed by bringing an inputtool such as a finger of a user or a touch pen into contact with thetouch panel, an input position is detected to be outputted. Sincedisplay devices having such a touch panel do not require an input devicesuch as a keyboard, a mouse, or a keypad, they are widely used inportable information terminals such as a mobile phone in addition tocomputers.

As one of detecting systems for detecting a contact position at which afinger of a user or the like has comes into contact with a touch panel,there is an electrostatic capacitance system. In a touch panel using thecapacitance type, a plurality of capacitive elements composed of a pairof electrodes disposed to face each other via a dielectric layer,namely, a driving electrode and a detecting electrode, is provided inplane of the touch panel. When an input action has been performed bybringing such an input tool as a finger of a user or a touch pen intocontact with a capacitive element, a capacitance is added to thecapacitive element, so that a detected capacitance is changed, which isutilized to detect the input position.

In Japanese Patent Application Laid-Open Publication No. 2012-73783(Patent Document 1), there is described a display device of a so-called“in-cell type” where a liquid crystal display device composed of liquidcrystal display elements and a touch-detecting device of a capacitancetype are integrated with each other. Further, in the Patent Document 1,there is such a description that common electrodes for display which arealso used as driving electrodes of the touch-detecting device arearranged side by side extending in one direction, while detectingelectrodes of the touch-detecting device are arranged side by side so asto extend in a direction intersecting with the common electrodes.

In Japanese Patent Application Laid-Open Publication No. 2012-43298(Patent Document 2), there is described a technique where in an inputdevice, a plurality of lower transparent electrodes extending in a firstdirection are arranged in a second direction orthogonal to the firstdirection, and a plurality of upper transparent electrodes extending inthe second direction are arranged in the first direction.

In Japanese Patent Application Laid-Open Publication No. 2012-14329(Patent Document 3), there is described a technique of detecting aninput position in an input device according to a self-capacitance systemwhere the number of electrodes used for sensing is one. Further, in thePatent Document 3, there is a description that the electrode used forsensing has an isosceles trapezoid having an upper side, a lower sideand two oblique sides.

SUMMARY

In the input device provided in the display device of an in-cell typedescribed in the Patent Document 1, the driving electrode has a functionserving as a driving electrode of the input device and a functionserving as a common electrode of the display device. Further, in thedisplay device, an image is displayed by applying a voltage betweencommon electrodes and pixel electrodes disposed to face each other viaan insulating film, but it is necessary to control a voltage applied atthe displaying time for each pixel, so that it is undesirable that twocommon electrodes adjacent to each other overlap with one pixelelectrode in a plan view. Therefore, the width of the driving electrodeis the integral multiple of an arrangement period or each width of pixelelectrodes, and the integer corresponds to the number of pixels per onedriving electrode.

However, such a case may take place that the number of pixel electrodes,namely the number of pixels, in the arrangement direction of the drivingelectrodes are determined depending on the specification required as thedisplay device and the number of pixels in the arrangement direction ofthe driving electrodes and the number of pixels in the arrangementdirection of the driving electrodes cannot be evenly divided by thenumber of pixels per one driving electrode. Here, since a broken numberdue to the indivisibility is allocated to, for example, a drivingelectrode at one end in the arrangement of driving electrodes, the widthof a certain driving electrode is sometimes different from the widths ofthe other driving electrodes.

In such a case, the area of a portion of a detecting electrodeoverlapping with the driving electrode having the different width isdifferent from the area of a portion of the detecting electrodeoverlapping with each of the other electrodes. Therefore, anelectrostatic capacitance between the driving electrode having thedifferent width and the detecting electrode cannot be made equal to anelectrostatic capacitance between each of the other driving electrodesand the detecting electrode. Therefore, a difference, namely, atolerance, of the detected capacitance detected on the driving electrodehaving the different width to the upper limit or the lower limit of anADC (analog-to-digital converter) range becomes small, so that a noiseimmunity of the detected capacitance may lower.

Further, even in an input device used as a single unit and an inputdevice provided in a display device of an on-cell type where the displaydevice and the input device are provided as units separated from eachother, the width of a certain driving electrode is different from thewidths of the other driving electrodes due to an arrangement constraintor the like. In such a case, it is also impossible to make theelectrostatic capacitance between the driving electrode having thedifferent width and the detecting electrode equal to the electrostaticcapacitance between each of the other driving electrodes and thedetecting electrode. Therefore, the tolerance of the detectedcapacitance detected on the driving electrode having the different widthto the upper limit or the lower limit of the ADC range becomes small,which may result in lowering of the noise immunity of the detectedcapacitance.

The present invention has been made in order to solve the problem in aconventional art such as described above, and an object thereof is toprovide an input device which can inhibit the noise immunity of thedetected capacitance from lowering on the driving electrode having awidth different from the widths of the other driving electrodes, and adisplay device provided with the input device.

The typical ones of the inventions disclosed in the present applicationwill be briefly described as follows.

An input device of a typical embodiment includes: a plurality of firstelectrodes extending in a first direction, respectively, and arranged ina second direction intersecting with the first direction in a plan view;a second electrode arranged outside one side of an arrangement of theplurality of first electrodes and extending in the first direction in aplan view; and a plurality of third electrodes extending in the seconddirection, respectively, and arranged in the first direction in a planview. In the input device, an input position is detected based upon afirst electrostatic capacitance between the third electrode and thefirst electrode and a second electrostatic capacitance between the thirdelectrode and the second electrode, a first width of the secondelectrode in the second direction is smaller than a second width of thefirst electrode in the second direction, and the third electrodeincludes a first expanding portion for expanding the area of the thirdelectrode on an opposite side of the plurality of first electrodesinterposing the second electrode in a plan view.

In addition, an input device of a typical embodiment includes: aplurality of first electrodes extending in a first direction,respectively, and arranged in a second direction intersecting with thefirst direction in a plan view; a second electrode arranged outside oneside of an arrangement of the plurality of first electrodes or in themiddle of the arrangement of the plurality of first electrodes andextending in the first direction in a plan view; and a plurality ofthird electrodes extending in the second direction, respectively, andarranged in the first direction in a plan view. In the input device, aninput position is detected based upon a first electrostatic capacitanceformed at a first intersection portion between the third electrode andthe first electrode and a second electrostatic capacitance formed at asecond intersection portion between the third electrode and the secondelectrode, a first width of the second electrode in the second directionis different from a second width of the first electrode in the seconddirection, the third electrode includes a first expanding portion forexpanding the area of the third electrode at the second intersectionportion, and the area of the first expanding portion is adjusted suchthat the area of a portion of the third electrode overlapping with thesecond electrode approaches the area of a portion of the third electrodeoverlapping with the first electrode in a plan view.

Moreover, an input device of a typical embodiment includes: a pluralityof first electrodes extending in a first direction, respectively, andarranged in a second direction intersecting with the first direction ina plan view; a second electrode arranged outside one side of anarrangement of the plurality of first electrodes or in the middle of thearrangement of the plurality of first electrodes and extending in thefirst direction in a plan view; and a plurality of third electrodesextending in the second direction, respectively, and arranged in thefirst direction in a plan view. In the input device, an input positionis detected based upon a first electrostatic capacitance formed at afirst intersection portion between the third electrode and the firstelectrode and a second electrostatic capacitance formed at a secondintersection portion between the third electrode and the secondelectrode, a first width of the second electrode in the second directionis larger than a second width of the first electrode in the seconddirection, the third electrode includes a first expanding portion forexpanding the area of the third electrode at the first intersectionportion, and the area of the first expanding portion is adjusted suchthat the area of a portion of the third electrode overlapping with thesecond electrode approaches the area of a portion of the third electrodeoverlapping with the first electrode.

The effects obtained by typical aspects of the present invention will bebriefly described below.

According to the representative embodiment, in the input device and thedisplay device provided with the input device, the noise immunity of thedetected capacitance can be prevented or inhibited from lowering on thedriving electrode having a width different from the widths of the otherdriving electrodes.

Additional features and advantages are described herein, and will beapparent from the following Detailed Description and the figures.

BRIEF DESCRIPTION OF THE FIGURES

FIG. 1 is an explanatory diagram showing a schematic configuration of atouch panel of a capacitance type;

FIG. 2 is an explanatory diagram showing an example of a relationshipbetween a driving waveform applied to the touch panel shown in FIG. 1and a signal waveform outputted from the touch panel;

FIG. 3 is an explanatory diagram schematically showing one example ofarrangements of driving electrodes and detecting electrodes shown inFIG. 1;

FIG. 4 is a plan view showing a configuration of one example of adisplay device of a first embodiment;

FIG. 5 is a cross-sectional view showing a configuration of one exampleof the display device of the first embodiment;

FIG. 6 is a cross-sectional view showing a configuration of one exampleof the display device of the first embodiment;

FIG. 7 is a plan view schematically showing an arrangement of drivingelectrodes and detecting electrodes in a touch panel provided in thedisplay device of the first embodiment;

FIG. 8 is a plan view schematically showing a first modification exampleof the arrangement of driving electrodes and detecting electrodes in atouch panel provided in the display device of the first embodiment;

FIG. 9 is a plan view schematically showing a second modificationexample of the arrangement of driving electrodes and detectingelectrodes in a touch panel provided in the display device of the firstembodiment;

FIG. 10 is a plan view schematically showing a third modificationexample of the arrangement of driving electrodes and detectingelectrodes in a touch panel provided in the display device of the firstembodiment;

FIG. 11 is a plan view schematically showing a fourth modificationexample of the arrangement of driving electrodes and detectingelectrodes in a touch panel provided in the display device of the firstembodiment;

FIG. 12 is a plan view schematically showing a fifth modificationexample of the arrangement of driving electrodes and detectingelectrodes in a touch panel provided in the display device of the firstembodiment;

FIG. 13 is a plan view schematically showing an arrangement of drivingelectrodes and detecting electrodes in a touch panel provided in thedisplay device of a first comparative example;

FIG. 14 is a graph showing a detected capacitance detected when adriving voltage is applied to each of a plurality of driving electrodesin the first comparative example;

FIG. 15 is a graph showing a detected capacitance detected when adriving voltage is applied to each of a plurality of driving electrodesin the first to fourth comparative examples;

FIG. 16 is a plan view schematically showing an arrangement of drivingelectrodes and detecting electrodes in a touch panel provided in thedisplay device of a second embodiment;

FIG. 17 is a plan view schematically showing a first modificationexample of an arrangement of driving electrodes and detecting electrodesin a touch panel provided in the display device of a second embodiment;

FIG. 18 is a plan view schematically showing a second modificationexample of the arrangement of driving electrodes and detectingelectrodes in the touch panel provided in the display device of thesecond embodiment;

FIG. 19 is a plan view schematically showing a third modificationexample of the arrangement of driving electrodes and detectingelectrodes in the touch panel provided in the display device of thesecond embodiment;

FIG. 20 is a plan view schematically showing a fourth modificationexample of the arrangement of driving electrodes and detectingelectrodes in the touch panel provided in the display device of thesecond embodiment;

FIG. 21 is a plan view schematically showing a fifth modificationexample of the arrangement of driving electrodes and detectingelectrodes in the touch panel provided in the display device of thesecond embodiment;

FIG. 22 is a plan view schematically showing a sixth modificationexample of the arrangement of driving electrodes and detectingelectrodes in the touch panel provided in the display device of thesecond embodiment;

FIG. 23 is a plan view schematically showing an arrangement of drivingelectrodes and detecting electrodes in a touch panel provided in adisplay device of a third embodiment;

FIG. 24 is a plan view schematically showing a first modificationexample of the arrangement of driving electrodes and detectingelectrodes in the touch panel provided in a display device of the thirdembodiment;

FIG. 25 is a plan view schematically showing a second modificationexample of the arrangement of driving electrodes and detectingelectrodes in the touch panel provided in a display device of the thirdembodiment;

FIG. 26 is a plan view schematically showing a third modificationexample of the arrangement of driving electrodes and detectingelectrodes in the touch panel provided in a display device of the thirdembodiment;

FIG. 27 is a plan view schematically showing a fourth modificationexample of the arrangement of driving electrodes and detectingelectrodes in the touch panel provided in a display device of the thirdembodiment;

FIG. 28 is a plan view schematically showing a fifth modificationexample of the arrangement of driving electrodes and detectingelectrodes in the touch panel provided in a display device of the thirdembodiment;

FIG. 29 is a plan view schematically showing a sixth modificationexample of the arrangement of driving electrodes and detectingelectrodes in the touch panel provided in a display device of the thirdembodiment;

FIG. 30 is a plan view schematically showing an arrangement of drivingelectrodes and detecting electrodes in a touch panel provided in thedisplay device of a second comparative example;

FIG. 31 is a graph showing a detected capacitance detected when adriving voltage is applied to each of a plurality of driving electrodesin the second comparative example;

FIG. 32 is a plan view schematically showing an arrangement of drivingelectrodes and detecting electrodes in a touch panel provided in thedisplay device of a second embodiment;

FIG. 33 is a plan view showing a configuration of one example of a touchpanel of a fourth embodiment;

FIG. 34 is a cross-sectional view showing a configuration of one exampleof the touch panel of the fourth embodiment;

FIG. 35 is a cross-sectional view showing a configuration of one exampleof a display device of the fourth embodiment;

FIG. 36 is a perspective view representing an appearance of a televisionas one example of an electronic device of a fifth embodiment;

FIG. 37 is a perspective view representing an appearance of a digitalcamera as one example of the electronic device of the fifth embodiment;

FIG. 38 is a perspective view representing an appearance of anotebook-type personal computer (laptop) as one example of theelectronic device of the fifth embodiment;

FIG. 39 is a perspective view representing an appearance of a videocamera as one example of the electronic device of the fifth embodiment;

FIG. 40 is a perspective view representing an appearance of a mobilephone as one example of the electronic device of the fifth embodiment;

FIG. 41 is a perspective view representing an appearance of a mobilephone as one example of the electronic device of the fifth embodiment;and

FIG. 42 is a perspective view representing an appearance of a smartphoneas one example of the electronic device of the fifth embodiment.

DETAILED DESCRIPTION

In the embodiments described below, the invention will be described in aplurality of sections or embodiments when required as a matter ofconvenience. However, these sections or embodiments are not irrelevantto each other unless otherwise stated, and the one relates to the entireor a part of the other as a modification example, details, or asupplementary explanation thereof.

Also, in the embodiments described below, when referring to the numberof elements (including number of pieces, values, amount, range, and thelike), the number of the elements is not limited to a specific numberunless otherwise stated or except the case in which the number isapparently limited to a specific number in principle. The number largeror smaller than the specified number is also applicable.

Further, in the embodiments described below, it goes without saying thatthe components (including element steps) are not always indispensableunless otherwise stated or except the case in which the components areapparently indispensable in principle. Similarly, in the embodimentsdescribed below, when the shape of the components, positional relationthereof, and the like are mentioned, the substantially approximate andsimilar shapes and the like are included therein unless otherwise statedor except the case in which it is conceivable that they are apparentlyexcluded in principle. The same goes for the numerical value and therange described above.

Hereinafter, embodiments of the present invention will be described indetail with reference to the accompanying drawings. Note that componentshaving the same function are denoted by the same reference symbolsthroughout the drawings for describing the embodiments, and a repetitivedescription thereof is omitted. In addition, the description of the sameor similar portions is not repeated in principle unless particularlyrequired in the following embodiments.

Also, in some drawings used in the embodiments, hatching may be usedeven in a plan view so as to make the drawings easy to see. Also, evenin plan views, hatching may be used so as to make the drawing easy tosee.

(First Embodiment)

<Operating Principle of Input Device of Capacitance Type>

First of all, a basic operating principle of an input device called“touch panel” or “touch sensor” of a capacitance type will be described.FIG. 1 is an explanatory diagram showing a schematic configuration of atouch panel of a capacitance type. Further, FIG. 2 is an explanatorydiagram showing an example of a relationship between a driving waveformapplied to the touch panel shown in FIG. 1 and a signal waveformoutputted from the touch panel. Furthermore, FIG. 3 is an explanatorydiagram schematically showing one example of arrangements of drivingelectrodes and detecting electrodes shown in FIG. 1.

A touch panel TP1 of a capacitance type as an input device has aplurality of driving electrodes Tx and a plurality of detectingelectrodes Rx. The driving electrodes Tx and the detecting electrodes Rxare disposed so as to face each other via a dielectric layer DL, andcapacitive elements C1 are formed by the driving electrodes Tx, thedielectric layer DL, and the detecting electrodes Rx.

A driving waveform DW which is a rectangular wave, for example, such asthat shown in FIG. 2, is applied to the driving electrode Tx from adriving circuit DR1 for an input device as a voltage for detection of aninput position, namely, a driving voltage. For example, as shown in FIG.2, current corresponding to the driving waveform DW and the capacitiveelement C1 shown in FIG. 1 flows from the detecting electrode Rx and asignal waveform SW is outputted therefrom. The signal waveform SWoutputted from the detecting electrode Rx is outputted into a detectioncircuit DT1 (see FIG. 1) which detects the input position. The detectioncircuit DT1 is provided with an ADC (analog-to-digital converter), sothat the signal waveform SW outputted from the detecting electrode Rx,namely, the detected capacitance, is converted from an analog signal toa digital signal by the ADC for processing.

Here, as shown in FIG. 1, when an input tool CMD having one end beingconnected to a ground potential, such as a finger of a user or a touchpen is brought close to or is brought into contact with the detectingelectrode Rx of the touch panel TP1, a capacitance of the input tool CMDis added to the capacitive element C1 at a position close to the inputtool CMD. Therefore, a signal waveform SW1, namely, the detectedcapacitance, outputted from the detecting electrode Rx disposed at aposition close to the input tool CMD is smaller than the signalwaveforms SW2, namely, the detected capacitances outputted from thedetecting electrodes Rx disposed at the other positions (for example,see FIG. 2).

Therefore, in the detection circuit DT1, signal waveforms SW, namely,detected capacitances, respectively transmitted from the plurality ofthe detecting electrodes Rx, are monitored, namely, measured, and theposition of the input tool CMD can be identified or detected based uponthe change amount of the signal waveforms SW, namely, the detectedcapacitances. For example, a threshold value is preliminarily set to thechange amount of the signal waveform SW, namely, the detectedcapacitance, and the position of the input tool CMD can be outputtedwith reference to position data of the detection electrode Rx exceedingthe threshold value. Further, for example, the values of the signalwaveforms SW, namely, the detected capacitances can be directly comparedwith the threshold value.

Note that, a phenomenon that the capacitance of the input tool CMD isadded to the capacitive element C1 occurs even when the input tool CMDand the detecting electrode Rx have approached each other in addition tothe case in which the input tool CMD and the detecting electrode Rs havecome into contact with each other. Therefore, it is unnecessary toexpose the detecting electrodes Rx to a face on which the input tool CMDis disposed, for example, the detecting electrodes Rx can be protectedby disposing a cover member between the detecting electrodes Rx and theinput tool CMD.

Furthermore, as the method of monitoring, namely, measuring, the signalwaveform, namely the detected capacitance, there are variousmodification examples, for example, a method of measuring a voltagevalue generated at the detecting electrode Rx, or a method of measuringan integrated quantity of current per unit time flowing in the detectioncircuit DT1 can be used.

Regarding respective plane arrangements of the driving electrodes Tx andthe detecting electrodes Rx, for example, as shown in FIG. 3, thedriving electrodes Tx and the detecting electrodes Rx can be disposedalternately so as to intersect with each other (preferably, beorthogonal to each other) in a band shape. In this case, a drivingwaveform DW (see FIG. 2) is applied to the plurality of drivingelectrodes Tx sequentially, and the change amount of the signal waveformSW (see FIG. 2) is determined for each intersection portion at which thedriving electrode Tx and the detecting electrode Rx intersect with eachother.

Note that the details of the arrangements of the driving electrodes Txand the detecting electrodes Rx will be described later.

<Configuration of Display Device>

Next, a configuration of a display device of a first embodiment will bedescribed. FIG. 4 is a plan view showing a configuration of one exampleof the display device of the first embodiment. FIG. 5 and FIG. 6 arecross-sectional views showing a configuration of one example of thedisplay device of the first embodiment. FIG. 5 is a cross-sectional viewtaken along the line A-A in FIG. 4. Further, FIG. 6 schematically showsa cross-sectional view of a main part shown in FIG. 5 in a furtherenlarged fashion.

A display device LCD1 of the first embodiment is a display device with atouch-detecting function. Further, the display device LCD1 of the firstembodiment is a display device with a touch-detecting function of aso-called “in-cell type” where a liquid crystal display device providedwith liquid crystal elements as display elements and an input devicecomposed of a touch panel TP1 of a capacitance type have been integratedwith each other.

In the liquid crystal display device, as a system of applying electricfield in order to change orientations of liquid crystal molecules in aliquid crystal layer functioning as a display image forming sectiondescribed later, two systems described below are mainly used. As a firstsystem, a so-called vertical-electric-field mode in which electric fieldis applied in a thickness direction of a liquid crystal display device,namely, in an off-plane direction is used. Further, as a second system,a so-called horizontal-electric-field mode where electric field isapplied in a plane direction of a liquid crystal display device, namely,in an in-plane direction is used. As the horizontal-electric-field mode,for example, an IPS (In-Plane Switching) mode, an FFS (Fringe FieldSwitching) mode, or the like is used. In the following, as one example,the display device LCD1 of an in-cell type in which a liquid crystaldisplay device of the FFS mode and an input device composed of a touchpanel TP1 are integrated with each other will be described.

As shown in FIG. 4 and FIG. 5, the display device LCD1 includes asubstrate 11, a substrate 12 arranged to face the substrate 11, and aliquid crystal layer 13 arranged between the substrate 11 and thesubstrate 12. The substrate 12 is disposed on a display surface side ofthe display device LCD1, while the substrate 11 is disposed on the sideopposite to the display surface side.

As shown in FIG. 6, the substrate 11 has a front surface 11 a positionedon the substrate 12 side, and a rear surface 11 positioned on theopposite side of the front surface 11 a. The substrate 11 is used as acircuit board in which various electrodes and wirings, thin-filmtransistors (TFTs), and the like are formed. The substrate is made ofglass, for example.

A common electrode 14 is disposed on the substrate 11, namely, on thefront surface 11 a side of the substrate 11 for each of a plurality ofpixels. The common electrode 14 is an electrode for supplying a commonvoltage to each plurality of pixels, and it is composed of a transparentconductive film having translucency, namely, a transparent conductivefilm, for example, ITO (Indium Tin Oxide) or the like. The term “havingtranslucency” or “transparent” means that the transmittance of lightwithin a visible light range having, for example, a wavelength of 550 nmis, for example, 80% or higher.

As shown in FIG. 4, the common electrodes 14 are arranged side by sideso as to extend in one direction within an area where the display deviceLCD1 performs displaying, namely, a display area EA1 which is an areawhere a plurality of pixels are arranged in a matrix fashion. Here, thecommon electrodes 14 are disposed within the display area EA1 in asection perpendicular to an extension direction (X-axis directiondescribed later with reference to FIG. 7) of the common electrodes 14.On the other hand, as shown in FIG. 4, the common electrodes 14 may beformed such that both ends thereof extend outside the display area EA1.Note that, details of the shape of the common electrode 14 will bedescribed later.

An insulating film 15 is formed on the common electrodes 14. Further,pixel electrodes 16 are disposed on the insulating film 15 correspondingto a plurality of pixels disposed within the display area EA1,respectively. The pixel electrodes 16 are arranged in a matrix fashionor in an array fashion corresponding to the plurality of pixels,respectively, and they face the common electrodes 14 via the insulatingfilm 15. That is, the common electrodes 14 and the pixel electrodes 16are arranged so as to face each other via the insulating film 15. Thepixel electrode 16 is an electrode for supplying a voltage as a pixelsignal for performing display for each pixel, and it is composed of atransparent conductive film having translucency, namely, a transparentconductive film, for example, ITO or the like.

Although not illustrated, an active element such as a TFT is formed onthe substrate 11, namely, on the front surface 11 a side of thesubstrate 11 corresponding to each pixel. Further, a display driver fordriving the pixel electrodes 16 and source lines for supplying pixelsignals to the pixel electrodes 16, wirings for such as gate lines fordriving TFTs are formed on the substrate 11, namely, the front surface11 a side of the substrate 11. According to such a configuration, avoltage is applied to each pixel electrode 16 for a display period inthe display device LCD1.

The substrate 12 has a front surface 12 a positioned on the displaysurface side and a rear surface 12 b positioned on the opposite side ofthe front surface 12 a, and the rear surface 12 b of the substrate 12faces the front surface 11 a of the substrate 11. Note that, since theabove-described common electrodes 14 and pixel electrodes 16 are formedon the rear surface 12 b side of the substrate 12, the common electrodes14 and pixel electrodes 16 are arranged between the substrate 11 and thesubstrate 12.

A color filter 17 is formed on the rear surface 12 b of the substrate12. The color filter 17 is constituted by arranging three color filterlayers of, for example, red (R), green (G), and blue (B) periodically.In a color display device, one picture element or one pixel isconstituted by utilizing sub-pixels of three colors of, for example, thered (R), green (G), and blue (B) as one set.

The liquid crystal layer 13 is provided between the substrate 11 and thesubstrate 12. The liquid crystal layer 13 functions as a display imageforming section which forms a display image by application of voltagesfor display between the pixel electrodes 16 and the common electrode 14.The liquid crystal layer 13 is constituted to modulate light passingthrough the liquid crystal layer 13 in response to a state of electricfield applied, and in the first embodiment, as described above, a liquidcrystal LC corresponding to the FFS mode can be used. Note that,although not illustrated, oriented films are disposed between the liquidcrystal layer 13 and the substrate 11 and between the liquid crystallayer 13 and the substrate 12, respectively. The liquid crystal layer 13is sealed between the substrate 11 and the substrate 12 by a seal 18.

A light source LS and a polarization plate PL1 for filtering light whichhas been generated from the light source LS are provided on the rearsurface 11 b side of the substrate 11 in the display device LCD1. On theother hand, a polarization plate PL2 for filtering light which haspassed through the substrate 12 is provided on the front surface 12 aside of the substrate 12.

A wiring board 21 is formed on the front surface 11 a of the substrate11. The wiring board 21 is, for example, a so-called flexible wiringboard where a plurality of wirings is formed in a resin film, which canbe freely deformed in response to the shape of an arrangement place ofthe flexible wiring board. Wirings 21 a are formed in the wiring board21. One end of the wiring 21 a is electrically connected to a pluralityof pixel electrodes 16, and the other end of the wiring 21 a iselectrically connected to a driving circuit DR2. The driving circuit DR2supplies a driving potential for image display to the pixel electrode16.

A displaying method of a color image performed by the display deviceLCD1 shown in FIG. 4 to FIG. 6 is, for example, as described below. Thatis, light emitted from the light source LS is filtered by thepolarization plate PL1 to pass through the polarization plate PL1 toenter the liquid crystal layer 13. The light which has entered theliquid crystal 13 is propagated in the liquid crystal layer 13 in adirection from the substrate 11 toward the substrate 12 to be emittedfrom the substrate 12 while a polarization state thereof is changed inresponse to anisotropy of the refractive index of the liquid crystal LC.Here, a liquid crystal orientation is controlled by electric fieldformed by application of voltages to the pixel electrodes 16 and thecommon electrodes 14, and the liquid crystal layer 13 functions as anoptical shutter. That is, in the liquid crystal layer 13, thetransmittance of light can be controlled for each sub-pixel. Light whichhas reached the substrate 12 is subjected to a color filteringprocessing in the color filter 17 formed on the substrate 12 to beemitted from the front surface 12 a. Further, light which has beenemitted from the front surface 12 a is filtered by the polarizationplate PL2 to reach a viewer VW.

<Configuration of Touch Panel>

Subsequently, a configuration of the touch panel TP1 serving as theinput device and provided in the display device LCD1 will be describedwith reference to FIG. 4 to FIG. 6.

As described with reference to FIG. 1, the touch panel TP1 serving asthe input device has a plurality of driving electrodes Tx and aplurality of detecting electrodes Rx. Further, the display device LCD1is a liquid crystal display device of an in-cell type. Therefore, thecommon electrodes 14 of the display device LCD1 are used as the drivingelectrodes Tx of the touch panel TP1.

As described with reference to FIG. 4, the common electrodes 14 arearranged within the display area EA1 which is an area on which thedisplay device LCD1 performs displaying, but since the common electrodes14 are also used as the driving electrodes Tx, they are also disposedwithin a detection area EA2 which is an area where the touch panel TP1detects an input position. That is, as shown in FIG. 4, the commonelectrodes 14 serving as the driving electrodes Tx are arranged side byside within the detection area EA1 so as to extend in one direction.Here, the common electrodes 14 serving as the driving electrodes Tx aredisposed within the detection area EA2 in a section perpendicular to theextension direction (X-axis direction described with reference to FIG.7) of the common electrodes 14. On the other hand, as shown in FIG. 4,the common electrodes 14 serving as the driving electrodes Tx may beformed such that both ends thereof extend outside the detection areaEA2.

Further, since the display device LCD1 is the liquid crystal displaydevice of an in-cell type, the detection area EA2 which is the areawhere the touch panel detects a position coincides with the display areaEA1 which is the area where the display device performs displaying. Asdescribed later in a fourth embodiment, however, when the display deviceis a display device of an on-cell type, the detection area EA2 which isthe area where the touch panel detects a position may not coincide withthe display area EA1 which is the area where the display device performsdisplaying.

Further, details of the shape of the common electrode 14, namely, thedriving electrode Tx in a plan view will be described later.

A plurality of detecting electrodes Rx is formed on the front surface 12a of the substrate 12. The plurality of detecting electrodes Rx are eachcomposed of a transparent conductive film having translucency, namely, atransparent conductive film, for example, ITO (Indium Tin Oxide) or thelike. Note that details of the shape of the detecting electrode Rx in aplan view will be described later.

As described above, the wiring board 21 is formed on the front surface11 a of the substrate 11. Wirings 21 b are formed in the wiring board21. One end of the wiring 21 b is electrically connected to each of theplurality of common electrodes 14, while the other end of the wiring 21b is electrically connected to the driving circuit DR1. The drivingcircuit DR1 applies the driving waveform DW for input position detectiondescribed with reference to FIG. 2 to the common electrodes 14 servingas the driving electrodes Tx.

For example, doubling of the common electrodes 14 and the drivingelectrodes Tx is made possible by dividing a certain period into a touchdetection period, namely, an input period and a display writing period.A whole thickness of the display device LCD1 can be made thin bydoubling of the common electrodes 14 of the display device LCD1 and thedriving electrodes Tx of the touch panel TP1.

A wiring board 22 is formed on the front surface 12 a of the substrate12. The wiring board 22 is, for example, a so-called flexible wiringboard in which a plurality of wirings are formed in a resin film and theflexible wiring board can be freely deformed in accordance with theshape of an arrangement place of the flexible wiring board. Wirings 22 aare formed in the wiring board 22. One end of the wiring 22 a iselectrically connected to each of the plurality of detecting electrodesRx, while the other end of the wiring 22 a is electrically connected tothe detection circuit DT1. The detection circuit DT1 detects an inputposition based upon a detection signal.

Note that, for example, since a light shielding layer is formed in anarea outside the display area EA1, namely, the detection area EA2, thedetecting electrodes Rx and the wiring boards 21 and 22 cannot beviewed.

<Arrangement of Driving Electrodes and Detecting Electrodes>

FIG. 7 is a plan view schematically showing an arrangement of drivingelectrodes and detecting electrodes in a touch panel provided in thedisplay device of the first embodiment.

As shown in FIG. 7, two directions intersecting with each other in aplan view are defined as an X-axis direction and a Y-axis direction.Further, as shown in FIG. 7, the X-axis direction and the Y-axisdirection are preferably orthogonal to each other. Note that, in thisspecification, the term “plan view” means a view from a directionperpendicular to the front surface 12 a (see FIG. 6) of the substrate12.

In the following explanation, for easy understanding, as one example, itis assumed that the number of driving electrodes Tx is 10 and the numberof detecting electrodes Rx is 10. However, the number of drivingelectrodes Tx is not limited to 10, and the number of detectingelectrodes Rx is not limited to 10. Therefore, the number of drivingelectrodes Tx can be set to M (M is an integer equal to 3 or more) whilethe number of detecting electrodes Rx can be set to N (N is an integerequal to 2 or more) (the same goes to modification examples of the firstembodiment, a second embodiment and a third embodiment, and modificationexamples thereof).

As shown in FIG. 7, as one example of the plurality of drivingelectrodes Tx, for example, it is assumed that ten driving electrodes Txindicated by Tx1, Tx2, . . . , Tx9, Tx10 are provided in the touch panelTP1. Further, as shown in FIG. 7, as one example of the plurality ofdetecting electrodes Rx, it is assumed that ten detecting electrodes Rxindicated by Rx1, Rx2, . . . , Rx10 are provided in the touch panel TP1.

In a plan view, the driving electrodes Tx1 to Tx10 extend in the X-axisdirection, respectively, and they are arranged in the Y-axis direction.That is, the driving electrodes Tx1 to Tx10 each extend in the X-axisdirection, and these driving electrodes Tx1 to Tx10 are spaced from oneanother and arranged in the Y-axis direction in the order to Tx1, Tx2, .. . , Tx9, Tx10. On the other hand, in a plan view, the detectingelectrodes Rx1 to Rx10 extend in the Y-axis direction, respectively, andthey are arranged in the X-axis direction. That is, the detectingelectrodes Rx1 to Rx10 each extend in the Y-axis direction, and thesedetecting electrodes Rx1 to Rx10 are spaced from one another andarranged in the X-axis direction in the order of Rx1, . . . , Rx10. Thedetecting electrodes Rx1 to Rx10 each intersect with the drivingelectrodes Tx1 to Tx10 in a plan view.

In a plan view, the respective widths of the driving electrodes Tx2 toTx9 in the Y-axis direction are represented by WD1, the width of thedriving electrode Tx1 in the Y-axis direction is represented by WD2, andthe width of the driving electrode Tx10 in the Y-axis direction isrepresented by WD3. Here, the respective widths WD1 of the drivingelectrodes Tx2 to Tx9 are equal to one another, the width WD2 of thedriving electrode Tx1 is smaller than the respective widths WD1 of thedriving electrodes Tx2 to Tx9, and the width WD3 of the drivingelectrode Tx10 is larger than the respective widths WD1 of the drivingelectrodes Tx2 to Tx9.

Further, the driving electrode Tx1 is arranged outside one side of anarrangement of the plurality of driving electrodes Tx2 to Tx9 in a planview, while the driving electrode Tx10 is arranged outside the otherside of the arrangement of the plurality of driving electrodes Tx2 toTx9 in the plan view.

Note that, although not illustrated in FIG. 7, the pixel electrodes 16(see FIG. 6) are arranged in the X-axis direction and in the Y-axisdirection corresponding to the plurality of pixels, respectively, to bedisposed in matrix.

As described with reference to FIG. 6, the common electrodes 14 have afunction to serve as the driving electrodes Tx of the touch panel TP1and a function to serve as the common electrodes 14 of the displaydevice LCD1. Further, since it is necessary to control a voltage appliedbetween the pixel electrodes 16 and the common electrodes 14 of thedisplay device LCD1 for each pixel, it is undesirable that two commonelectrodes adjacent to each other overlap with one pixel electrode in aplan view. Therefore, the respective widths WD1 of the drivingelectrodes Tx2 to Tx9 is an integral multiple (an integral multiple ofdouble or higher) of the arrangement period or the width of the pixelelectrodes in the Y-axis direction, and the integral number is thenumber of pixels per one driving electrode Tx. That is, each of thedriving electrodes Tx2 to Tx9 has a width to overlap with the pluralityof pixel electrodes arranged in the Y-axis direction in a plan view.

However, the number of pixel electrodes, namely, the number of pixels,in the Y-direction is determined according to the specification requiredas the display device. Therefore, such a case sometimes occurs that thenumber of pixels in the Y-axis direction cannot be evenly divided by thenumber of pixels per one driving electrodes Tx. In such a case, a brokennumber due to the indivisibility is allocated to the driving electrodesTx on both sides of the arrangement of the driving electrodes Tx in adivisional fashion, and the widths obtained by multiplying therespective allocated broken numbers by the arrangement period or thewidth of the pixel electrodes in the Y-axis direction are set as thewidths WD2 and WD3 of the driving electrodes Tx1 and Tx10, respectively.Thus, the widths WD2 and WD3 of the driving electrodes Tx1 and Tx10become smaller than the respective widths WD1 of the driving electrodesTx2 to Tx9.

For example, such a case is considered that 89 pixels are arranged inthe Y-axis direction and one driving electrode Tx is arranged for eachten pixels. In this case, 9 pixels of a reminder occurring when 89pixels are divided into each 10 pixels are divided into 4 pixels and 5pixels, and the 4 pixels and the 5 pixels are allocated to the drivingelectrodes on both ends of the arrangement of the driving electrodes Tx.Therefore, for example, the respective widths WD1 of the drivingelectrodes Tx2 to Tx9 can be made equal to the width corresponding to 10pixels, the width WD2 of the driving electrode Tx1 can be made equal tothe width corresponding to 4 pixels, and the width WD3 of the drivingelectrode Tx10 can be made equal to the width corresponding to 5 pixels.

Since the detecting electrodes Rx1 to Rx10 can be set to have the sameshape, representing the detecting electrodes Rx1 to Rx10, the detectingelectrode Rx1 is explained as the detecting electrode Rx (the same goesto modification examples of the first embodiment, a second embodimentand a third embodiment, and modification examples of the second andthird embodiment).

An intersection portion between each of the driving electrodes Tx2 toTx9 and the detecting electrode Rx is represented as CR1, anintersection portion between the driving electrode Tx1 and the drivingelectrode Tx is represented as CR2, and an intersection portion betweenthe driving electrode Tx10 and the driving electrode Tx is representedas CR3. Further, an electrostatic capacitance between each of thedriving electrodes Tx2 to Tx9 and the detecting electrode Rx isrepresented as CP1, an electrostatic capacitance between the drivingelectrode Tx1 and the detecting electrode Rx is represented as CP2, andan electrostatic capacitance between the driving electrode Tx10 and thedetecting electrode Rx is represented as CP3. Here, an input position isdetected based upon the electrostatic capacitances CP1, CP2, and CP3.

The detecting electrode Rx includes a main body portion BD, and aplurality of overhang portions OH1 and overhang portions OH2 to OH5. Themain body portion BD extends in the Y-axis direction, and the width ofthe main body portion BD in the X-axis direction is represented as WB.Note that, in FIG. 7, the overhang portions OH1 formed in the areaprovided with the driving electrode Tx2 and the overhang portions OH2and OH3 are hatched.

Further, in the following, the case in which the overhang portions OH1to OH5 have a rectangular shape is described as an example, but theoverhang portions OH1 to OH5 may have a triangular shape, asemi-circular shape, or the other various shapes (the same goes tomodification examples of the first embodiment, a second embodiment and athird embodiment, and modification examples thereof).

In a plan view, the plurality of overhang portions OH1 are formed insidethe areas provided with the driving electrodes Tx2 to Tx9, namely,inside the plurality of intersection portions CR1 to project in apositive direction and in a negative direction of the X-axis direction,respectively. The overhang portion OH1 is an expanding portion forexpanding the area of the detecting electrode Rx as compared with thecase in which the overhang portion OH1 is not formed. Further, the areasof the plurality of overhang portions OH1 are preferably equal to oneanother. Therefore, since the shapes of the overhang portions OH1 have aperiodicity to be inconspicuous, visibility of the display device LCD1can be improved, and the electrostatic capacitances between the drivingelectrodes Tx2 to Tx9 and the detecting electrode Rx can be made equalto one another, respectively.

Note that, the positive direction and the negative direction of theX-axis direction are directions opposed to each other along the X-axisdirection, the positive direction of the X-axis direction is a directionfrom the detecting electrode Rx1 toward the detecting electrode Rx10,and the negative direction of the X-axis direction is a direction fromthe detecting electrode Rx10 toward the detecting electrode Rx1.

In a plan view, the overhang portions OH2 are formed inside the areaprovided with the driving electrode Tx1, namely inside the intersectionportion CR2 to project from the main body portion BD in the positivedirection and the negative direction of the X-axis direction,respectively. The overhang portion OH2 is an expanding portion forexpanding the area of the detecting electrode Rx as compared with thecase in which the overhang portion OH2 is not formed. Further, the areaof the overhang portion OH2 is preferably equal to the area of theoverhang portion OH1. Therefore, since the shape of the overhang portionOH2 can be made identical to the shape of the overhang portion OH1 sothat the overhang portion OH2 becomes inconspicuous, visibility of thedisplay device LCD1 can be improved.

In a plan view, the overhang portions OH3 are formed inside the areaprovided with the driving electrode Tx10, namely inside the intersectionportion CR3 to project from the main body portion BD in the positivedirection and the negative direction of the X-axis direction,respectively. The overhang portion OH3 is an expanding portion forexpanding the area of the detecting electrode Rx as compared with thecase in which the overhang portion OH3 is not formed. Further, the areaof the overhang portion OH3 is preferably equal to the area of theoverhang portion OH1. Therefore, since the shape of the overhang portionOH3 can be made equal to the shape of the overhang portion OH1 so thatthe overhang portion OH3 becomes inconspicuous, visibility of thedisplay device LCD1 can be improved.

In a plan view, the overhang portions OH4 are formed on the sideopposite to the plurality of driving electrodes Tx2 to Tx9 via thedriving electrode Tx1, namely on the positive direction side of theY-axis direction to the driving electrode Tx1, to project from the mainbody portion BD in the positive direction and the negative direction ofthe X-axis direction, respectively. The overhang portion OH4 is anexpanding portion for expanding the area of the detecting electrode Rxas compared with the case in which the overhang portion OH4 is notformed.

In a plan view, the overhang portions OH5 are formed on the sideopposite to the plurality of driving electrodes Tx2 to Tx9 via thedriving electrode Tx10, namely on the negative direction side of theY-axis direction to the driving electrode Tx10, to project from the mainbody portion BD in the positive direction and the negative direction ofthe X-axis direction, respectively. The overhang portion OH5 is anexpanding portion for expanding the area of the detecting electrode Rxas compared with the case in which the overhang portion OH5 is notformed.

Note that, the positive direction and the negative direction of theY-axis direction are opposite directions to each other along the Y-axisdirection, the positive direction of the Y-axis direction is a directionfrom the driving electrode Tx10 toward the driving electrode Tx1, andthe negative direction of the Y-axis direction is a direction from thedriving electrode Tx1 toward the driving electrode Tx10.

The length of the overhang portion OH1 in the X-axis direction isrepresented as LN1, and the width of the overhang portion OH1 in theY-axis direction is represented as WR1. Further, the length of theoverhang portion OH2 in the X-axis direction is represented as LN2, andthe width of the overhang portion OH2 in the Y-axis direction isrepresented a WR2. Further, the length of the overhang portion OH3 inthe X-axis direction is represented as LN3, and the width of theoverhang portion OH3 in the Y-axis direction is represented as WR3.

In the first embodiment, for example, it is assumed that the length LN1of the overhang portion OH1, the length LN2 of the overhang portion OH2,and the length LN3 of the overhang portion OH3 are equal to one another.Furthermore, for example, it is assumed that the width WR1 of theoverhang portion OH1, the width WR2 of the overhang portion OH2, and thewidth WR3 of the overhang portion OH3 are equal to one another. Here, anarea SO2 of the overhang portion OH2 which is a product of the lengthLN2 and the width WN2 becomes equal to an area SO1 of the overhangportion OH1 which is a product of the length LN1 and the width WR1. Anarea SO3 of the overhang portion OH3 which is a product of the lengthLN3 and the width WR3 becomes equal to the area SO1 of the overhangportion OH1 which is the product of the length LN1 and the width WR1.

Further, an area SB1 of a portion of the main body portion BDoverlapping with each of the driving electrodes Tx2 to Tx9 isrepresented by the product of the width WB and the width WD1. An areaSB2 of a portion of the main body portion BD overlapping with thedriving electrode Tx1 is represented by the product of the width WB andthe width WD2, and an area SB3 of a portion of the main body portion BDoverlapping with the driving electrode Tx10 is represented as theproduct of the width WB and the width WD3. Therefore, an area S1 of aportion of the detecting electrode Rx overlapping with each of thedriving electrodes Tx2 to Tx9 is represented by the following equation(1)S1=SB1+SO1×2=WB×WD1+LN1×WR1×2  Equation (1)

Further, an area S2 of a portion of the detecting electrode Rxoverlapping with the driving electrode Tx1 is represented by thefollowing Equation (2).S2=SB2+SO2×2=WB×WD2+LN2×WR2×2  Equation (2)

Further, an area S3 of a portion of the detecting electrode Rxoverlapping with the driving electrode Tx10 is represented by thefollowing Equation (3).S3=SB3+SO3×2=WB×WD3+LN3×WR3×2  Equation (3)

As described above, since the width WD2 is smaller than the width WD1,and the width WD2 is smaller than the width WD1, the area SB2 is smallerthan the area SB1 and the area SB3 is smaller than the area SB1.Further, as described above, the area SO2 is equal to the area SO1, andthe area SO3 is equal to the area SO1. Therefore, according to theabove-described Equation (1) and Equation (2), the area S2 becomessmaller than the area S1, and the electrostatic capacitance CP2 betweenthe driving electrode Tx1 and the detecting electrode Rx becomes smallerthan the electrostatic capacitance CP1 between each of the drivingelectrodes Tx2 to Tx9 and the detecting electrode Rx. Further, accordingto the above-described Equation (1) and Equation (3), the area S3becomes smaller than the area S1, and the electrostatic capacitance CP3between the driving electrode Tx10 and the detecting electrode Rxbecomes smaller than the electrostatic capacitance CP1 between each ofthe driving electrodes Tx2 to Tx9 and the detecting electrode Rx.

In the first embodiment, however, the overhang portions OH4 have beenformed. Further, although the overhang portions OH4 do not overlap withthe driving electrode Tx1 in a plan view, they may be disposed in thevicinity of the driving electrode Tx1. Therefore, by forming theoverhang portions OH4, the electrostatic capacitance CP2 between thedriving electrode Tx1 and the detecting electrode Rx can be increasedand adjustment can be performed such that the electrostatic capacitanceCP2 approaches the electrostatic capacitance CP1 between each of thedriving electrodes Tx2 to Tx9 and the detecting electrode Rx.

Further, in the first embodiment, the overhang portions OH5 have beenformed. Further, though the overhang portions OH5 do not overlap withthe driving electrode Tx10 in a plan view, they may be disposed in thevicinity of the driving electrode Tx10. Therefore, by forming theoverhang portions OH5, the electrostatic capacitance CP3 between thedriving electrode Tx10 and the detecting electrode Rx can be increasedand adjustment can be performed such that the electrostatic capacitanceCP3 approaches the electrostatic capacitance CP1 between each of thedriving electrodes Tx2 to Tx9 and the detecting electrode Rx.

That is, when driving electrodes having a width smaller than the widthsof the other driving electrodes are disposed on both sides of thearrangement of the other driving electrodes, adjustment can be performedsuch that the electrostatic capacitance between the driving electrodehaving the smaller width and the detecting electrode approaches theelectrostatic capacitance between each of the other driving electrodesand the detecting electrode.

Note that, the expression “the electrostatic capacitance CP2 approachesthe electrostatic capacitance CP1” means that the ratio of theelectrostatic capacitance CP2 to the electrostatic capacitance CP1approaches 1, and it preferably means that the ratio of theelectrostatic capacitance CP2 to the electrostatic capacitance CP1becomes 0.9 to 1.1. Furthermore, the expression “the electrostaticcapacitance CP3 approaches the electrostatic capacitance CP1” means thatthe ratio of the electrostatic capacitance CP3 to the electrostaticcapacitance CP1 approaches 1, and it preferably means that the ratio ofthe electrostatic capacitance CP3 to the electrostatic capacitance CP1becomes 0.9 to 1.1. That is, the expression “the second electrostaticcapacitance approaches the first electrostatic capacitance” means thatthe ratio of the second electrostatic capacitance to the firstelectrostatic capacitance approaches 1, and it preferably means that theratio of the second electrostatic capacitance to the first electrostaticcapacitance becomes 0.9 to 1.1 (the same goes to modification examplesof the first embodiment, a second embodiment and modification examplesthereof, and a third embodiment and modification examples thereof, afourth embodiment, and a fifth embodiment).

The driving electrodes Tx1 to Tx10 are disposed within theabove-described display area EA1 in a section perpendicular to theX-axis direction. Further, the overhang portions OH4 and OH5 aredisposed in an area OEA outside the display area EA1 in a plan view.Further, since the display area EA1 is an area formed with pixels, it isnot shielded from light, but the area OEA outside the display area EA1is shielded from light by a light-shielding layer (not shown).Therefore, the overhang portions OH4 and OH5 are shielded from light bya light-shielding layer (not shown). Therefore, since the pattern shapesof the overhang portions OH4 and OH5 are not viewed, visibility of thedisplay device can be improved.

That is, in the first embodiment, in order to adjust the electrostaticcapacitance between the driving electrode having a width smaller thanthe widths of the other driving electrodes and the detecting electrode,the expanding portion for expanding the area of the detecting electrodeis provided outside the display area in a plan view.

In a plan view, the overhang portions OH4 can be brought close to thedriving electrode Tx1 up to a position where the outer peripheralportions of the overhang portions OH4 come into contact with the drivingelectrode Tx1, namely, a position where a distance DS1 shown in FIG. 7becomes 0. Here, the distance DS1 is a distance between an outerperiphery of the overhang portion OH4 on the side of the negativedirection of the Y-axis direction and an outer periphery of the drivingelectrode Tx1 on the side of the positive direction of the Y-axisdirection. That is, the overhang portions OH4 are preferably formed suchthat outer peripheries of the overhang portions OH4 on the side of thenegative direction of the Y-axis direction come into contact with theouter periphery of the driving electrodes Tx1 on the side of thepositive direction of the Y-axis direction in a plan view. Therefore,adjustment can be performed such that the electrostatic capacitance CP2between the driving electrode Tx1 and the detecting electrode Rxapproaches the electrostatic capacitance CP1 between each of the drivingelectrodes Tx2 to Tx9 and the detecting electrode Rx, while visibilityof the display device is improved.

Further, in a plan view, the overhang portions OH5 can be brought closeto the driving electrode Tx10 up to a position where the outerperipheral portions of the overhang portions OH5 come in contact withthe driving electrode Tx10, namely, a position where a distance DS2shown in FIG. 7 becomes 0. Here, the distance DS2 is a distance betweenan outer periphery of the overhang portion OH5 on the side of thepositive direction of the Y-axis direction and an outer periphery of thedriving electrode Tx10 on the side of the negative direction of theY-axis direction. That is, the overhang portions OH5 are preferablyformed such that outer peripheries of the overhang portions OH5 on theside of the positive direction of the Y-axis direction contact with theouter periphery of the driving electrodes Tx10 on the side of thenegative direction of the Y-axis direction in a plan view. Therefore,adjustment can be performed such that the electrostatic capacitance CP3between the driving electrode Tx10 and the detecting electrode Rxapproaches the electrostatic capacitance CP1 between each of the drivingelectrodes Tx2 to Tx9 and the detecting electrode Rx, while visibilityof the display device is improved.

Note that, in FIG. 7, the case that both ends of each of the drivingelectrodes Tx1 to Tx10 are positioned inside the display area EA1,namely, the detection area EA2 is shown. As shown in FIG. 4, however,the both ends of each of the driving electrodes Tx1 to Tx10 may bepositioned outside the display area EA1, namely, the detection area EA2(the same goes to modification examples of the first embodiment, asecond embodiment and a third embodiment, and modification examples ofthe second and third embodiments).

<First Modification Example of Arrangement of Driving Electrodes andDetection Electrodes>

FIG. 8 is a plan view schematically showing an arrangement of drivingelectrodes and detecting electrodes in the touch panel provided in thedisplay device of the first embodiment. FIG. 8 shows an example in whichthe width of the driving electrode Tx1 is smaller than the respectivewidths of the driving electrodes Tx2 to Tx9 but the width of the drivingelectrode Tx10 is equal to the respective widths of the drivingelectrodes Tx2 to Tx9. Note that, members of a touch panel TP1 shown inFIG. 8 which have the same functions as those of the members of thetouch panel TP1 shown in FIG. 7 are denoted by the same referencenumerals and repetitive descriptions thereof will be omitted.

In the first modification example, the respective widths WD1 of thedriving electrodes Tx2 to Tx10 are equal to one another, and the widthof the driving electrode WD2 of the driving electrode Tx1 is smallerthan the respective widths of the driving electrodes Tx2 to Tx10.Further, the driving electrode Tx1 is arranged outside one side of thearrangement of the plurality of driving electrodes Tx2 to Tx10 in a planview.

In this modification example, when the number of pixels along the Y-axisdirection cannot be evenly divided by the number of pixels per onedriving electrode Tx, a broken number which has occurred due to theindivisibility is allocated to one end of the arrangement of the drivingelectrodes Tx, and the width obtained by multiplying the allocatedbroken number by the arrangement period or the width of the pixelelectrodes is set as the width WD2 of the driving electrode Tx1.

An intersection portion between each of the driving electrodes Tx2 toTx10 and the detecting electrode Rx is represented as CR1, and anintersection portion between the driving electrode Tx1 and the detectingelectrode Rx is represented as CR2. Further, an electrostaticcapacitance between each of the driving electrodes Tx2 to Tx10 and thedetecting electrode Rx is represented as CP1, and an electrostaticcapacitance between the driving electrode Tx1 and the detectingelectrode Rx is represented as CP2. Here, an input position is detectedbased upon the electrostatic capacitances CP1 and CP2.

The detecting electrode Rx includes the main body portion BD, theplurality of overhang portions OH1, and the overhang portions OH2 andOH4, but it does not include the overhang portions OH3 and OH5 (see FIG.7).

In a plan view, the plurality of overhang portions OH1 are formed insidethe areas provided with the driving electrodes Tx2 to Tx10,respectively, namely inside the plurality of intersection potions CR1 soas to project from the main body portion BD in the positive directionand in the negative direction of the X-axis direction, respectively. Theoverhang portion OH1 is an expanding portion for expanding the area ofthe detecting electrode Rx as compared with the case in which theoverhang portion OH1 is not formed. Further, the areas of the respectiveoverhang portions OH1 of the plurality of driving electrodes Tx2 to Tx10are preferably equal to one another. Therefore, since the shapes of theoverhang portions OH1 have a periodicity to be inconspicuous, visibilityof the display device LCD1 can be improved, and the electrostaticcapacitances between the driving electrodes Tx2 to Tx10 and thedetecting electrode Rx can be made equal to each other, respectively.

The overhang portion OH2 in the first modification example may be madeequal to the overhang portion OH2 in the first embodiment. Further, theoverhang portion OH4 in the first modification example may be made equalto the overhang portion OH4 in the first embodiment.

In the first modification example, the electrostatic capacitance betweenthe driving electrode Tx1 and the detecting electrode Rx can beincreased by forming the overhang portions OH4 in the same manner as thefirst embodiment. Therefore, adjustment can be performed such that theelectrostatic capacitance between the driving electrode Tx1 and thedetecting electrode Rx approaches the electrostatic capacitance betweeneach of the other driving electrodes Tx2 to Tx10 and the detectingelectrode Rx.

That is, even when the driving electrode having a width smaller than thewidths of the other driving electrodes is disposed only outside one sideof the arrangement of the other driving electrodes, adjustment can beperformed such that the electrostatic capacitance between the drivingelectrode having the smaller width and the detecting electrodeapproaches the electrostatic capacitance between each of the otherdriving electrodes and the detecting electrode.

<Second Modification Example and Third Modification Example ofArrangement of Driving Electrodes and Detecting Electrode>

FIG. 9 is a plan view schematically showing a second modificationexample of an arrangement of driving electrodes and detecting electrodesin the touch panel provided in the display device of the firstembodiment. FIG. 10 is a plan view schematically showing a thirdmodification example of an arrangement of driving electrodes anddetecting electrodes in the touch panel provided in the display deviceof the first embodiment. FIG. 9 and FIG. 10 show examples in which theoverhang portions OH1 to OH5 project toward one side of the main bodyportion BD but not toward other side thereof. Note that, respectiveportions of the touch panels TP1 other than the overhang portions OH1 toOH5 in the second modification example and the third modificationexample are identical to those of the touch panel TP1 in the firstembodiment. Therefore, the respective portions of the touch panels shownin FIG. 9 and FIG. 10 other than the overhang portions OH1 to OH5, whichare members having the same functions as those of members of the touchpanel TP1 shown in FIG. 7 are denoted by the same reference numerals,and repetitive descriptions thereof will be omitted.

In the second modification example shown in FIG. 9, in a plan view, theplurality of overhang portions OH1, and the overhang portions OH2 to OH5are formed to project in the positive direction of the X-axis directionfrom the main body portion BD, and the detecting electrodes Rx have acomb-like shape.

Further, in the third modification example shown in FIG. 10, theplurality of overhang portions OH1, and the overhang portions OH2 to OH5are formed to project in the positive direction or the negativedirection of the X-axis direction from the main body portion BD, and thedetecting electrodes Rx have a comb-like shape. In the thirdmodification example, the detecting electrodes having the overhangportions OH1 to OH5 projecting from the main body portion BD in thepositive direction of the X-axis direction and the detecting electrodeshaving the overhang portions OH1 to OH5 projecting from the main bodyportion BD in the negative direction of the X-axis direction arealternately arranged in the X-axis direction.

In each of the second modification example and the third modificationexample, also, adjustment can be performed by formation of the overhangportions OH4 in the same manner as the first embodiment such that theelectrostatic capacitance between the driving electrode Tx1 and thedetecting electrode Rx approaches the electrostatic capacitance betweeneach of the driving electrodes Tx2 to Tx9 and the detecting electrodeRx. Further, in each of the second modification example and the thirdmodification example, also, adjustment can be performed by formation ofthe overhang portions OH5 in the same manner as the first embodimentsuch that the electrostatic capacitance between the driving electrodeTx10 and the detecting electrode Rx approaches the electrostaticcapacitance between each of the driving electrodes Tx2 to Tx9 and thedetecting electrode Rx.

<Fourth Modification Example of Arrangement of Driving Electrodes andDetecting Electrodes>

FIG. 11 is a plan view schematically showing a fourth modificationexample of an arrangement of driving electrodes and detecting electrodesin the touch panel provided in the display device of the firstembodiment. FIG. 11 shows an example in which each of a plurality ofdetecting electrodes has a plurality of main body portions. Note that,in FIG. 11, illustration of the substrate 12, the display area EA1, thedetecting area EA2 and the area OEA (see FIG. 7) is omitted. Further,respective portions of the touch panel other than the detectingelectrodes Rx1 to Rx10, namely, the detecting electrodes Rx, in thefourth modification example are identical to respective portions of thetouch panel TP1 in the first embodiment. Therefore, the respectiveportions of the touch panel shown in FIG. 11 other than the detectingelectrodes, which are members having the same functions as those ofmembers of the touch panel TP1 shown in FIG. 7 are denoted by the samereference numerals, and repetitive descriptions thereof will be omitted.

In the fourth modification example shown in FIG. 11, the detectingelectrode Rx includes three main body portions BD1, BD2, and BD3, aplurality of connecting portions CN1 and connecting portions CN2 to CN5,and a plurality of overhang portions OH1 and overhang portions OH2 toOH5.

The three main body portions BD1, BD2 and BD3 each extend in the Y-axisdirection, and they are arranged in the X-axis direction. The three mainbody portions BD1, BD2 and BD3 are united in one piece on the side ofthe negative direction of the Y-axis direction, and they areelectrically connected to one another on the side of the negativedirection of the Y-axis direction. Note that, the present invention isnot limited to the case in which the detecting electrode Rx includes thethree main body portions BD1, BD2, and BD3, but it may include two, fouror more main body portions.

In a plan view, each of the plurality of connecting portions CN1 isformed inside an area provided with each of the driving electrodes Tx2to Tx9 so as to connect the main body portions BD1, BD2 and BD3. In aplan view, the connecting portion CN2 is formed inside an area providedwith the driving electrode Tx1 so as to connect the main body portionsBD1, BD2 and BD3. In a plan view, the connecting portion CN3 is formedinside an area provided with the driving electrode Tx10 so as to connectthe main body portions BD1, BD2 and BD3. Each of the connecting portionsCN1 to CN3 is an expanding portion for expanding the area of thedetecting electrode Rx as compared with a case in which each of theconnecting portions CN1 to CN3 is not formed.

In a plan view, the plurality of overhang portions OH1 are respectivelyformed inside the areas provided with the driving electrodes Tx2 to Tx9so as to project from the main body portion BD1 in the negativedirection of the X-axis direction and project from the main body portionBD3 in the positive direction of the X-axis direction. The overhangportion OH1 is an expanding portion for expanding the area of thedetecting electrode Rx as compared with a case in which the overhangportion OH1 is not formed.

Further, preferably, the respective areas of the plurality of connectingportions CN1 are equal to one another, and the respective areas of theplurality of overhang portions OH1 are equal to one another. Therefore,since the shapes of the connecting portions CN1 and the overhangportions OH1 have a periodicity to be inconspicuous, visibility of thedisplay device LCD1 can be improved, and the electrostatic capacitancesbetween the respective driving electrodes Tx2 to Tx9 and the detectingelectrode Rx can be made equal to each other.

In a plan view, the overhang portions OH2 are formed inside the areaprovided with the driving electrode Tx1 so as to project from the mainbody portion BD1 in the negative direction of the X-axis direction andproject from the main body portion BD3 in the positive direction of theX-axis direction, respectively. The overhang portion OH2 is an expandingportion for expanding the area of the detecting electrode Rx as comparedwith a case in which the overhang portion OH2 is not formed.

Preferably, the area of the connecting portion CN2 is equal to the areaof the connecting portion CN1, and the area of the overhang portion OH2is equal to the area of the overhang portion OH1. Therefore, since theshape of the connecting portion CN2 can be made identical to the shapeof the connecting portion CN1 and the shape of the overhang portion OH2can be made identical to the shape of the overhang portion OH1, theconnecting portion CN2 and the overhang portion OH2 becomeinconspicuous, and thus visibility of the display device LCD1 can beimproved.

In a plan view, the overhang portions OH3 are formed inside the areaprovided with the driving electrode Tx10 so as to project from the mainbody portion BD1 in the negative direction of the X-axis direction andproject from the main body portion BD3 in the positive direction of theX-axis direction, respectively. The overhang portion OH3 is an expandingportion for expanding the area of the detecting electrode Rx as comparedwith a case in which the overhang portion OH3 is not formed.

Further, preferably, the area of the connecting portion CN3 is equal tothe area of the connecting portion CN1 and the area of the overhangportion OH3 is equal to the area of the overhang portion OH1. Therefore,since the shape of the connecting portion CN3 can be made identical tothe shape of the connecting portion CN1 and the shape of the overhangportion OH3 can be made identical to the shape of the overhang portionOH1, so that the connecting portion CN3 and the overhang portion OH3become inconspicuous, visibility of the display device LCD1 can beimproved.

In a plan view, the connecting portion CN4 is formed so as to connectthe main body portions BD1, BD2 and BD3 on the side opposite to theplurality of driving electrodes Tx2 to Tx9 via the driving electrodeTx1, namely, on the side of the positive direction of the Y-axisdirection to the driving electrode Tx1. The connecting portion CN4 is anexpanding portion for expanding the area of the detecting electrode Rxas compared with a case in which the connecting portion CN4 is notformed.

In a plan view, the overhang portions OH4 are formed so as to projectfrom the main body portion BD1 in the negative direction of the X-axisdirection and project from the main body portion BD3 in the positivedirection of the X-axis direction, respectively, on the side opposite tothe plurality of driving electrodes Tx2 to Tx9 via the driving electrodeTx1, namely, on the side of the positive direction of the Y-axisdirection to the driving electrode Tx1. The overhang portion OH4 is anexpanding portion for expanding the area of the detecting electrode Rxas compared with a case in which the overhang portion OH4 is not formed.

In a plan view, the connecting portion CN5 is formed so as to connectthe main body portions BD1, BD2 and BD3 on the side opposite to theplurality of driving electrodes Tx2 to Tx9 via the driving electrodeTx10, namely, on the side of the negative direction of the Y-axisdirection to the driving electrode Tx10. The connecting portion CN5 isan expanding portion for expanding the area of the detecting electrodeRx as compared with a case in which the connecting portion CN5 is notformed.

In a plan view, the overhang portions OH5 are formed so as to projectfrom the main body portion BD1 in the negative direction of the X-axisdirection and project from the main body portion BD3 in the positivedirection of the X-axis direction, respectively, on the side opposite tothe plurality of driving electrodes Tx2 to Tx9 via the driving electrodeTx10, namely, on the side of the negative direction of the Y-axisdirection to the driving electrode Tx10. The overhang portion OH5 is anexpanding portion for expanding the area of the detecting electrode Rxas compared with a case in which the overhang portion OH5 is not formed.

In the fourth modification example, adjustment can be performed byformation of the connecting portion CN4 and the overhang portions OH4 inthe same manner as the first embodiment such that the electrostaticcapacitance between the driving electrode Tx1 and the detectingelectrode Rx approaches the electrostatic capacitance between each ofthe driving electrodes Tx2 to Tx9 and the detecting electrode Rx.Further, adjustment can be performed by formation of the connectingportion CN5 and the overhang portions OH5 in the same manner as thefirst embodiment such that the electrostatic capacitance between thedriving electrode Tx10 and the detecting electrode Rx approaches theelectrostatic capacitance between each of the driving electrodes Tx2 toTx9 and the detecting electrode Rx.

<Fifth Modification Example of Arrangement of Driving Electrodes andDetecting Electrodes>

FIG. 12 is a plan view schematically showing a fifth modificationexample of an arrangement of driving electrodes and detecting electrodesin the touch panel provided in the display device of the firstembodiment. FIG. 12 shows an example in which each of a plurality ofdetecting electrodes has a plurality of main body portions. Note that,in FIG. 12, illustration of the substrate 12, the display area EA1, thedetecting area EA2 and the area OEA (see FIG. 7) is omitted. Further,respective portions of the touch panel other than the detectingelectrodes Rx1 to Rx10, namely, the detecting electrodes Rx, in thefifth modification example are identical to respective portions of thetouch panel TP1 in the first embodiment. Therefore, the respectiveportions of the touch panel shown in FIG. 12 other than the detectingelectrodes Rx, which are members having the same functions as those ofmembers of the touch panel TP1 shown in FIG. 7 are denoted by the samereference numerals, and repetitive descriptions thereof will be omitted.

In the fifth modification example shown in FIG. 12, the detectingelectrode Rx includes two main body portions BD1 and BD2, and connectingportions CN4 and CN5.

The two main body portions BD1 and BD2 each extend in the Y-axisdirection, and they are arranged in the X-axis direction. The two mainbody portions BD1 and BD2 are united into one piece on the side of thenegative direction of the Y-axis direction, and they are electricallyconnected to each other on the side of the negative direction of theY-axis direction. Note that, the present invention is not limited to thecase the detecting electrode Rx includes two main body portions BD1 andBD2, but the detecting electrodes Rx may include three or more main bodyportions.

In a plan view, the connecting portion CN4 is formed so as to connectthe main body portions BD1 and BD2 on the side opposite to the pluralityof driving electrodes Tx2 to Tx9 via the driving electrode Tx1, namely,on the side of the positive direction of the Y-axis direction to thedriving electrode Tx1. The connecting portion CN4 is an expandingportion for expanding the area of the detecting electrode Rx as comparedwith a case in which the connecting portion CN4 is not formed.

In a plan view, the connecting portion CN5 is formed so as to connectthe main body portions BD1 and BD2 on the side opposite to the pluralityof driving electrodes Tx2 to Tx9 via the driving electrode Tx10, namely,on the side of the negative direction of the Y-axis direction to thedriving electrode Tx10. The connecting portion CN5 is an expandingportion for expanding the area of the detecting electrode Rx as comparedwith a case in which the connecting portion CN5 is not formed.

On the other hand, as shown in FIG. 12, in a plan view, such aconfiguration can be adopted that, the connecting portion or theoverhang portion as the expanding portions for expanding the area of thedetecting electrode Rx is not formed inside the area provided with eachof the driving electrodes Tx1 to Tx10. In a plan view, such aconfiguration can be adopted that, the overhang portions projecting fromthe main body portion BD1 in the negative direction of the X-axisdirection and projecting from the main body portion BD2 in the positivedirection of the X-axis direction, respectively, are not formed on theside opposite to the plurality of driving electrodes Tx2 to Tx9 via thedriving electrode Tx1. Further, such a configuration can be adopted in aplan view, the overhang portions projecting from the main body portionBD1 in the negative direction of the X-axis direction and projectingfrom the main body portion BD2 in the positive direction of the X-axisdirection are not formed on the side opposite to the plurality ofdriving electrodes Tx2 to Tx9 via the driving electrode Tx10.

In the fifth embodiment, adjustment can be performed by forming theconnecting portions CN4 and CN5 in the same manner as the firstembodiment that the electrostatic capacitance between each of thedriving electrodes Tx1 and Tx10 and the detecting electrode Rxapproaches the electrostatic capacitance between each of the drivingelectrodes Tx2 to Tx9 and the detecting electrode Rx.

<Regarding Electrostatic Capacitance Between Driving Electrode andDetecting Electrode>

Next, the electrostatic capacitance between the driving electrode andthe detecting electrode will be described with reference to a firstcomparative example. FIG. 13 is a plan view schematically showing anarrangement of the driving electrodes and the detecting electrodes in atouch panel provided in a display device of the first comparativeexample.

In the first comparative example, it is assumed that the detectingelectrode Rx includes the main body portion BD and the overhang portionsOH1 to OH3, but it does not include the overhang portions OH4 and OH5.The main body portion BD extends in the Y-axis direction and the widthof the main body portion BD in the X-axis direction is represented asWB.

FIG. 14 is a graph showing a detected capacitance detected when adriving voltage has been applied to each of the plurality of drivingelectrodes in the first comparative example. In FIG. 14, a horizontalaxis represents a driving electrode applied with a driving voltage and avertical axis represents a detected capacitance. Further, in FIG. 14, arange of a detected capacitance which can be detected by the ADC,namely, a lower limit LL1 and an upper limit UL1 of the ADC range isshown. Further, the detected capacitance shown in FIG. 14 is equal tothe electrostatic capacitance between each of the driving electrodes Tx1to Tx10 and the detecting electrode Rx.

Note that respective potions of the touch panel TP100 other than thedetecting electrodes Rx1 to Rx10, namely, the detecting electrode Rx inthe first comparative example shown in FIG. 14 are identical to therespective portions of the touch panel TP1 other than the detectingelectrode Rx in the first embodiment shown in FIG. 7. Further,respective portions other than the touch panel TP100 in the displaydevice provided with the touch panel TP100 of the first comparativeexample are identical to the respective portions other than the touchpanel TP1 in the display device LCD1 shown in FIG. 6.

That is, in the first comparative example, also, the width WD2 of thedriving electrode Tx1 is smaller than the respective widths WD1 of thedriving electrodes Tx2 to Tx9 and the width WD3 of the driving electrodeTx10 is smaller than the respective widths WD1 of the driving electrodesTx2 to Tx9 in the same manner as the first embodiment.

Further, respective portions of the detecting electrode Rx in the firstcomparative example are identical to the respective portions of thedetecting electrode Rx in the first embodiment except for a point thatthe former detecting electrode Rx does not include the overhang portionsOH4 and OH5. That is, each of the plurality of overhang portions OH1 inthe first comparative example is identical to each of the plurality ofoverhang portions OH1 in the first embodiment. Further, the overhangportion OH2 in the first comparative example is identical to theoverhang portion OH2 in the first embodiment. Further, the overhangportion OH3 in the first comparative example is identical to theoverhang portion OH3 in the first embodiment.

Note that, in FIG. 13, the overhang portions OH1 formed inside the areaprovided with the driving electrode Tx2, and the overhang portions OH2and OH3 are hatched.

In the first comparative example, also, the width WD2 of the drivingelectrode Tx1 is smaller than the respective widths WD1 of the drivingelectrodes Tx2 to Tx9 in the same manner as the first embodiment.Therefore, the area S2 of a portion of the detecting electrode Rxoverlapping with the driving electrode Tx1 becomes smaller than the areaS1 of a portion of the detecting electrode Rx overlapping with each ofthe driving electrodes Tx2 to Tx9. Further, in the first comparativeexample, also, the width WD3 of the driving electrode Tx10 is smallerthan the respective widths WD1 of the driving electrodes Tx2 to Tx9 inthe same manner as the first embodiment. Therefore, the area S3 of aportion of the detecting electrode Rx overlapping with the drivingelectrode Tx10 becomes smaller than the area S1 of a portion of thedetecting electrode Rx overlapping with each of the driving electrodesTx2 to Tx9. Accordingly, the electrostatic capacitance between each ofthe driving electrodes Tx1 and Tx10 and the detecting electrode Rxbecomes smaller than the electrostatic capacitance between each of thedriving electrodes Tx2 to Tx9 and the detecting electrode Rx.

In the touch panel TP100 of the first comparative example, as shown inFIG. 14, the electrostatic capacitances, namely, the detectedcapacitances detected when a driving voltage has been applied to therespective driving electrodes Tx2 to Tx9 become a constant value CST1.

In the touch panel TP100 of the first comparative example, however, theelectrostatic capacitance, namely the detected capacitance detected whena driving voltage has been applied to each of the driving electrodes Tx1and Tx10 becomes smaller than the constant value CST1. When the detectedcapacitance becomes smaller than the constant value CST1, there is sucha possibility that the detected capacitance approaches the lower limitLL1 or becomes smaller than the lower limit LL1. That is, a difference,namely, a tolerance of the detected capacitance detected when thedriving voltage has been applied to each of the driving electrodes Tx1and Tx10 to the lower limit LL1 of the ADC range becomes small, so thata resistance of the detected capacitance to the noise, namely, a noiseimmunity of the detected capacitance lowers. As a result, in the touchpanel TP100 of the first comparative example, a position detectionaccuracy may be lowered or the position detection sensitivity may belowered on the driving electrodes Tx1 and Tx10 as compared with that onthe driving electrodes Tx2 to Tx9.

<Main Features and Advantageous Effects of the First Embodiment>

In the first embodiment and the first modification example to the fifthmodification example, the detecting electrode Rx is disposed on the sideopposite to the plurality of driving electrodes Tx2 to Tx9 via thedriving electrode Tx1 or the driving electrode Tx10, and it includes,for example, the overhang portions OH4 and OH4 or the connectingportions CN4 and CN5 as the expanding portions for expanding the area ofthe detecting electrode Rx. In the following, the overhang portions OH4and OH5 are described on behalf of the overhang portions OH4 and OH5 andthe connecting portions CN4 and CN5, but the overhang portions OH4 andOH5 cannot increase the areas of portions of the detecting electrode Rxoverlapping with the driving electrodes Tx1 and Tx10 in a plan view.

However, since each of the overhang portions OH4 and OH5 is disposed inthe vicinity of the driving electrode Tx1 or in the vicinity of thedriving electrode Tx10, the detected capacitance between each of thedriving electrodes Tx1 and Tx10 and the detecting electrode Rx can beincreased. Therefore, the electrostatic capacitance between each of thedriving electrodes Tx1 and Tx10 and the detecting electrode Rx can beprevented or inhibited from becoming smaller than the electrostaticcapacitance between each of the driving electrodes Tx2 to Tx9 and thedetecting electrode Rx.

FIG. 15 is a graph showing a detected capacitance detected when adriving electrode has been applied to each of the plurality of drivingelectrodes in Example 1 and Example 2 which are examples in the firstembodiment. In FIG. 15, a horizontal axis represents a driving electrodeapplied with a driving voltage, and a vertical axis represents adetected capacitance in the same manner as FIG. 14. Further, FIG. 15shows the range of the detected capacitance which can be detected by theADC, namely, the lower limit LL1 and the upper limit UL1 of the ADCrange like FIG. 14. Further, the detected capacitances shown in FIG. 15are equal to the electrostatic capacitances between the respectivedriving electrodes Tx1 to Tx10 and the detecting electrode Rx like thedetected capacitance shown in FIG. 14.

As shown in FIG. 15, it is assumed that the electrostatic capacitances,namely, the detected capacitances detected when a driving voltage hasbeen applied to the respective driving electrodes Tx2 to Tx9 also takethe constant value CST1 in Example 1 and Example 2.

Here, the respective areas of the overhang portions OH4 and OH5 arepreferably adjusted so that the electrostatic capacitances, namely, thedetected capacitances detected when a driving voltage has been appliedto the respective driving electrodes Tx1 and Tx10 fall within a range of±10% to the constant value CST1. The case in which the detectingelectrode Rx includes the overhang portions OH4 and OH5 thus adjusted isshown as Example 1 shown in FIG. 15.

In Example 1 shown in FIG. 15, a difference, namely, a tolerance, of thedetected capacitance detected when a driving voltage has been applied toeach of the driving electrodes Tx1 and Tx10 to the lower limit LL1 ofthe ADC range can be inhibited from becoming small as compared with thefirst comparative example shown in FIG. 14. A noise immunity of thedetected capacitance detected when a driving voltage has been applied toeach of the driving electrodes Tx1 and Tx10 can be inhibited fromlowering. As a result, a position detection accuracy can be prevented orinhibited from lowering and a position detection sensitivity can beprevented or inhibited from lowering on the driving electrodes Tx1 andTx10 as compared with that on the driving electrodes Tx2 to Tx9.Therefore, the position detection performance in the display device canbe improved.

Further, the areas of the overhang portions OH4 and OH5 are preferablyadjusted such that the detected capacitance detected when a drivingvoltage has been applied to each of the driving electrodes Tx1 and Tx10becomes the constant value CST1. The case in which the detectingelectrode Rx includes the overhang portions OH4 and OH5 thus adjusted isshown as Example 2 shown in FIG. 15.

In Example 2 shown in FIG. 15, the tolerance of the detected capacitancedetected when a driving voltage has been applied to each of the drivingelectrodes Tx1 and Tx10 to the lower limit LL1 of the ADC range can beinhibited further securely from becoming small. The noise immunity ofthe detected capacitance detected when a driving voltage has beenapplied to each of the driving electrodes Tx1 and Tx10 can be inhibitedfurther securely from lowering. As a result, a position detectionaccuracy can be prevented or inhibited further securely from loweringand a position detection sensitivity can be prevented or inhibitedfurther securely from lowering on the driving electrodes Tx1 and Tx10 ascompared with on the driving electrodes Tx2 to Tx9. Accordingly, theposition detection performance in the display device can be improved.

(Second Embodiment)

In the first embodiment, in a plan view, the expanding portion forexpanding the area of the detecting electrode is provided outside thedisplay area in order to adjust the electrostatic capacitance betweenthe driving electrode having a width smaller than those of the otherdriving electrodes and the detecting electrode. On the other hand, inthe second embodiment, in order to adjust the electrostatic capacitancebetween the driving electrode having a width smaller than those of theother driving electrodes and the detecting electrode, the expandingportion for expanding the area of the detecting electrode is provided onthe driving electrode having the smaller width in a plan view.

Since respective portions of the display device of the second embodimentother than a touch panel TP2 are identical to the respective portions ofthe display device of the first embodiment other than the touch panelTP1, descriptions of respective portions of the display device of thesecond embodiment other than a touch panel TP2 are omitted.

<Arrangement of Driving Electrodes and Detecting Electrodes>

FIG. 16 is a plan view schematically showing an arrangement of drivingelectrodes and detecting electrodes in a touch panel provided in thedisplay device of the second embodiment.

Note that, respective portions of the touch panel TP2 other than thedetecting electrodes Rx1 to Rx10, namely, the detecting electrodes Rx inthe second embodiment are identical to respective portions of the touchpanel TP1 in the first embodiment. Therefore, respective portions of thetouch panel TP2 shown in FIG. 16 other than the driving electrodes Rx,which have the same functions as those of the members of the touch panelTP1 shown in FIG. 7 are denoted by the same reference numerals, anddescriptions thereof are omitted.

In the second embodiment, the widths WD1 of the respective drivingelectrodes Tx2 to Tx9 are equal to one another in the same manner as thefirst embodiment. Further, the width WD2 of the driving electrode Tx1 issmaller than the respective widths WD1 of the driving electrodes Tx2 toTx9, and the width WD3 of the driving electrode Tx10 is smaller than therespective widths WD1 of the driving electrodes Tx2 to Tx9.

In the second embodiment, in the same manner as the first embodiment, anintersection portion between each of the driving electrodes Tx2 to Tx9and the detecting electrode Rx is represented as CR1, an intersectionportion between the driving electrode Tx1 and the detecting electrode Rxis represented as CR2, and an intersection portion between the drivingelectrode Tx10 and the detecting electrode Rx is represented as CR3.Further, the electrostatic capacitance between each of the drivingelectrodes Tx2 to Tx9 and the detecting electrode Rx, namely, theelectrostatic capacitance formed at the intersection portion CR1, isrepresented as CP1. Further, the electrostatic capacitance between thedriving electrode Tx1 and the detecting electrode Rx, namely, theelectrostatic capacitance formed at the intersection portion CR2, isrepresented as CP2, and the electrostatic capacitance between thedriving electrode Tx10 and the detecting electrode Rx, namely, theelectrostatic capacitance formed at the intersection portion CR3, isrepresented as CP3. Here, an input position is detected based upon theelectrostatic capacitances CP1, CP2, and CP3.

The detecting electrode Rx includes a main body portion BD, and aplurality of overhang portions OH1 and overhang portions OH2 and OH3.The main body portion BD extends in the Y-axis direction, and the widthof the main body portion BD in the X-axis direction is represented asWB. Note that, in FIG. 16, the overhang portions OH1 provided inside thearea provided with the driving electrode Tx2, and the overhang portionsOH2 and OH3 are hatched.

Each of the plurality of overhang portions OH1 in the second embodimentcan be made identical with each of the plurality of overhang portionsOH1 in the first embodiment.

In a plan view, the overhang portions OH2 are formed inside the areaprovided with the driving electrode Tx1, namely at the intersectionportion CR2, and overhang from the main body portion BD in the positivedirection and the negative direction of the X-axis direction,respectively. The overhang portion OH2 is an expanding portion forexpanding the area of the detecting electrode Rx as compared with thecase in which the overhang portion OH2 is not formed.

In a plan view, the overhang portions OH3 are formed inside the areaprovided with the driving electrode Tx10, namely at the intersectionportion CR3, and overhang from the main body portion BD in the positivedirection and the negative direction of the X-axis direction,respectively. The overhang portion OH3 is an expanding portion forexpanding the area of the detecting electrode Rx as compared with thecase in which the overhang portion OH3 is not formed.

In the second embodiment, also, the area of a portion of the detectingelectrode Rx overlapping with each of the driving electrodes Tx2 to Tx9is represented as S1, the area of a portion of the detecting electrodeRx overlapping with the driving electrode Tx1 is represented as S2, andthe area of a portion of the detecting electrode Rx overlapping with thedriving electrode Tx10 is represented as S3 in the same manner as thefirst embodiment. Here, the area of the overhang portion OH2 has beenadjusted such that the area S2 approaches the area S1, and the area ofthe overhang portion OH3 has been adjusted such that the area S3approaches the area S1. Further, preferably, the area of the overhangportion OH2 has been adjusted such that the area S2 becomes equal to thearea S1 and the area of the overhang portion OH3 has been adjusted suchthat the area S3 becomes equal to the area S1.

Note that, the expression “the area S2 approaches the area S1” meansthat the ratio of the area S2 to the area S1 approaches 1, and itpreferably means, for example, that the ratio of the area S2 to the areaS1 falls within the range of 0.9 to 1.1. Further, the expression “thearea S3 approaches the area S1” means that the ratio of the area S3 tothe area S1 approaches 1, and it preferably means, for example, that theratio of the area S3 to the area S1 falls within the range of 0.9 to1.1. That is, the expression “the second area approaches the first area”means that the ratio of the second area to the first area approaches 1,and it preferably means, for example, that the ratio of the second areato the first area falls within the range of 0.9 to 1.1 (the same goes tomodification examples of the second embodiment).

In the second embodiment, also, the length of the overhang portion OH1in the X-axis direction is represented as LN1, and the width of theoverhang portion OH1 in the Y-axis direction is represented as WR1 inthe same manner as the first embodiment. Further, the length of theoverhang portion OH2 in the X-axis direction is represented as LN2, andthe width of the overhang portion OH2 in the Y-axis direction isrepresented as WR2. Further, the length of the overhang portion OH3 inthe X-axis direction is represented as LN3, and the width of theoverhang portion OH3 in the Y-axis direction is represented as WR3.

In the second embodiment, also, for example, it is assumed in the samemanner as the first embodiment that the length LN1 of the overhangportion OH1, the length LN2 of the overhang portion OH2, and the lengthLN3 of the overhang portion OH3 are equal to each other. Here,adjustment has been performed such that the width WR2 of the overhangportion OH2 is larger than the width WR1 of the overhang portion OH1,and adjustment has been performed such that the width WR3 of theoverhang portion OH3 is larger than the width WR1 of the overhangportion OH1. That is, adjustment has been performed such that the areaSO2 of the overhang portion OH2 which is a product of the length LN2 andthe width WR2 becomes larger than the area SO1 of the overhang portionOH1 which is a product of the length LN1 and the width WR1. Adjustmenthas been performed such that the area SO3 of the overhang portion OH3which is a product of the length LN3 and the width WR3 becomes largerthan the area SO1 of the overhang portion OH1 which is a product of thelength LN1 and the width WR1.

Furthermore, the area SB1 of a portion of the main body portion BDoverlapping with each of the driving electrodes Tx2 to Tx9 isrepresented by a product of the width WB and the width WD1. The area SB2of a portion of the main body portion BD overlapping with the drivingelectrode Tx1 is represented by a product of the width WB and the widthWD2, and the area SB3 of a portion of the main body portion BDoverlapping with the driving electrode Tx10 is represented by a productof the width WB and the width WD3. Therefore, the area S1 of the portionof the detecting electrode Rx overlapping with each of the drivingelectrodes Tx2 to Tx9 is represented by the above-mentioned Equation(1). The area S2 of the portion of the detecting electrode Rxoverlapping with the driving electrode Tx1 is represented by theabove-mentioned Equation (2), and the area S3 of the portion of thedetecting electrode Rx overlapping with the driving electrode Tx10 isrepresented by the above-mentioned Equation (3).

As described above, since the width WD2 is smaller than the width WD1and the width WD3 is smaller than WD1, the area SB2 is smaller than thearea SB1 and the area SB3 is smaller than SB1. Therefore, when the areaSO2 of the overhang portion OH2 is equal to the area SO1 of the overhangportion OH1, the area S2 becomes smaller than the area S1, so that theelectrostatic capacitance between the driving electrode Tx1 and thedetecting electrode Rx becomes smaller than the electrostaticcapacitance between each of the driving electrodes Tx2 to Tx9 and thedetecting electrode Rx. Further, when the area SO3 of the overhangportion OH3 is equal to the area SO1 of the overhang portion OH1, thearea S3 becomes smaller than the area S1, so that the electrostaticcapacitance between the driving electrode Tx10 and the detectingelectrode Rx becomes smaller than the electrostatic capacitance betweeneach of the driving electrodes Tx2 to Tx9 and the detecting electrodeRx.

In the second embodiment, however, for example, since the width WR2 islarger than the width WR1, adjustment has been performed that the areaSO2 of the overhang portion OH2 becomes larger than the area SO1 of theoverhang portion OH1. Adjustment has been performed such that the areaS2 of the portion of the detecting electrode Rx overlapping with thedriving electrode Tx1 approaches the area S1 of the portion of thedetecting electrode Rx overlapping with each of the driving electrodesTx2 to Tx9. Therefore, adjustment can be performed such that theelectrostatic capacitance between the driving electrode Tx1 and thedetecting electrode Rx approaches the electrostatic capacitance betweeneach of the driving electrodes Tx2 to Tx9 and the detecting electrodeRx.

Further, in the second embodiment, for example, since the width WR3 islarger than the width WR1, adjustment has been performed that the areaSO3 of the overhang portion OH3 becomes larger than the area SO1 of theoverhang portion OH1. Adjustment has been performed such that the areaS3 of the portion of the detecting electrode Rx overlapping with thedriving electrode Tx10 approaches the area S1 of the portion of thedetecting electrode Rx overlapping with each of the driving electrodesTx2 to Tx9. Therefore, adjustment can be performed in such a manner thatthe electrostatic capacitance between the driving electrode Tx10 and thedetecting electrode Rx approaches the electrostatic capacitance betweeneach of the driving electrodes Tx2 to Tx9 and the detecting electrodeRx.

That is, in the second embodiment, adjustment has been performed suchthat the area of a portion of the detecting electrode overlapping withthe driving electrode having a width smaller than those of the otherdriving electrodes approaches the area of the portion of the detectingelectrode overlapping with each of the other driving electrodes in aplan view.

Further, in the second embodiment, when the driving electrodes having awidth smaller than those of the other driving electrodes are arranged onboth sides of an arrangement of the other driving electrodes, adjustmentcan be performed such that the electrostatic capacitance between each ofthe driving electrodes having the smaller width and the detectingelectrode approaches the electrostatic capacitance between each of theother driving electrodes and the detecting electrode.

Further, in the second embodiment, in order to adjust the electrostaticcapacitance between the driving electrode having the width smaller thanthose of the other driving electrodes and the detecting electrode, theexpanding portion for expanding the area of the detecting electrode isprovided inside the display area in a plan view.

<First Modification Example of Arrangement of Driving Electrodes andDetecting Electrodes>

FIG. 17 is a plan view schematically showing a first modificationexample of an arrangement of the driving electrodes and the detectingelectrodes in the touch panel provided in the display device of thesecond embodiment. FIG. 17 shows an example in which the width of thedriving electrode Tx1 is smaller than the respective widths of thedriving electrodes Tx2 to Tx9 but the width of the driving electrodeTx10 is equal to the respective widths of the driving electrodes Tx2 toTx9. Note that, members of the touch panel TP2 shown in FIG. 17 havingthe same functions as those of the members of the touch panel TP2 shownin FIG. 16 are denoted by the same reference numerals and descriptionsthereof are omitted.

In the first modification example, the respective widths WD1 of thedriving electrodes Tx2 to Tx10 are equal to one another and the widthWD2 of the driving electrode Tx1 is smaller than the respective widthsWD1 of the driving electrodes Tx2 to Tx10.

The detecting electrode Rx includes the main body portion BD, and theplurality of overhang portions OH1 and the overhang portions OH2, but itdoes not include the overhang portions OH3 (see FIG. 16). That is, theoverhang portions OH1 are formed inside an area provided with thedriving electrode Tx10.

Each of the plurality of overhang portions OH1 in the first modificationexample can be made identical to each of the plurality of overhangportions OH1 in the second embodiment. Further, the overhang portion OH2in the first modification example can be made identical to the overhangportion OH2 in the second embodiment.

In the first modification example, in the same manner as the secondembodiment, adjustment has been performed such that the area of theoverhang portion OH2 becomes larger than the area of the overhangportion OH1, and adjustment has been performed such that the area of aportion of the detecting electrode Rx overlapping with the drivingelectrode Tx1 approaches the area of a portion of the detectingelectrode Rx overlapping with each of the driving electrodes Tx2 toTx10. Therefore, adjustment can be performed such that the electrostaticcapacitance between the driving electrode Tx1 and the detectingelectrode Rx approaches the electrostatic capacitance between each ofthe driving electrodes Tx2 to Tx10 and the detecting electrode Rx.

That is, even when the driving electrode having a width smaller thanthose of the other driving electrodes is arranged only on one side ofthe arrangement of the other driving electrodes, adjustment can beperformed such that the electrostatic capacitance between the detectingelectrode having the smaller width and the detecting electrodeapproaches the electrostatic capacitance between each of the otherdriving electrodes and the detecting electrode.

<Second Modification Example of Arrangement of Driving Electrodes andDetecting Electrodes>

FIG. 18 is a plan view schematically showing a second modificationexample of an arrangement of the driving electrodes and the detectingelectrodes in the touch panel provided in the display device of thesecond embodiment. FIG. 18 shows an example in which the drivingelectrode having a width smaller than those of the other drivingelectrodes is not arranged outside of the arrangement of the otherdriving electrodes but it is arranged in the middle of the arrangementof the other driving electrodes. Note that, members of the touch panelTP2 shown in FIG. 18 having the same functions as those of the membersof the touch panel TP2 shown in FIG. 16 are denoted by the samereference numerals and descriptions thereof is omitted.

In the second modification example, in a plan view, the respectivewidths of the driving electrodes Tx1 to Tx3 and Tx5 to Tx10 in theY-axis direction are represented as WD1 and the width in the Y-axisdirection of the driving electrode Tx4 arranged in the middle ofarrangement of the driving electrodes is represented as WD2. Here, therespective widths WD1 of the driving electrodes Tx1 to Tx3 and Tx5 toTx10 are equal to one another, and the width WD2 of the drivingelectrode Tx4 is smaller than the respective widths WD1 of the drivingelectrodes Tx1 to Tx3 and Tx5 to Tx10.

For example, according to a specification required as a display deviceor the like, a driving electrode having a width obtained by multiplyinga broken number which has occurred due to the indivisibility of thenumber of pixels in the Y-axis direction by the arrangement period orthe width of pixel electrodes in the Y-axis direction is not arrangedoutside the arrangement of the driving electrodes but it is arranged inthe middle of the arrangement of the driving electrodes. In such a case,for example, the width WD2 of the driving electrode Tx4 which is thedriving electrode arranged in the middle of the arrangement of thedriving electrodes is made smaller than the respective widths WD1 of thedriving electrodes Tx1 to Tx3 and Tx5 to Tx10 which are the otherdriving electrodes.

Note that, the widths WD1 may also be made different between the drivingelectrodes Tx1 to Tx3 and the driving electrodes Tx5 to Tx10. Further,in the second modification example, the example in which the drivingelectrode having a width smaller than those of the other drivingelectrodes is arranged at the fourth position in the arrangement of thedriving electrodes is described, but the position of the drivingelectrode having the smaller width is not limited to the fourth positionbut it may be any position in the middle of the arrangement.

In the second modification example, the intersection portion betweeneach of the driving electrodes Tx1 to Tx3 and Tx5 to Tx10 and thedetecting electrode Rx is represented as CR1, and the intersectionportion between the driving electrode Tx4 and the detecting electrode Rxis represented as CR2. Further, the electrostatic capacitance betweeneach of the driving electrodes Tx1 to Tx3 and Tx5 to Tx10 and thedetecting electrode Rx is represented as CP1, and the electrostaticcapacitance between he driving electrode Tx4 and the detecting electrodeRx is represented as CP2. Here, an input position is detected based uponthe electrostatic capacitances CP1 and CP2.

Each of the plurality of overhang portions OH1 in the secondmodification example can be made equal to each of the plurality ofoverhang portions OH1 in the second embodiment. Furthermore, theoverhang portion OH2 in the second modification example may be madeequal to the overhang portion OH2 in the second embodiment.

In the second modification example, also, adjustment has been performedin the same manner as the second embodiment such that the area of theoverhang portion OH2 becomes larger than the area of the overhangportion OH1. Adjustment has been performed such that the area of aportion of the detecting electrode Rx overlapping with the drivingelectrode Tx4 approaches the area of a portion of the detectingelectrode Rx overlapping with each of the driving electrodes Tx1 to Tx3and Tx5 to Tx10.

<Third Modification Example and Fourth Modification Example ofArrangement of Driving Electrodes and Detecting Electrodes>

FIG. 19 is a plan view schematically showing a third modificationexample of arrangement of the driving electrodes and the detectingelectrodes in the touch panel provided in the display device of thesecond embodiment. FIG. 20 is a plan view schematically showing a fourthmodification example of arrangement of the driving electrodes and thedetecting electrodes in the touch panel provided in the display deviceof the second embodiment. FIG. 19 and FIG. 20 show examples where theoverhang portions OH1 to OH3 project to one side of the main bodyportion BD, but they do not project to the other side thereof. Notethat, respective portions of the touch panels TP2 other than theoverhang portions OH1 to OH3 in the third modification example and thefourth modification example are identical to respective portion of thetouch panel TP2 in the second embodiment. Therefore, respective portionsof the touch panels TP2 shown in FIG. 19 and FIG. 20 other than theoverhang portions OH1 to OH3, which are members having the samefunctions as those of members of the touch panel TP2 shown in FIG. 16are denoted by the same reference numerals, and repetitive descriptionsthereof will be omitted.

In the third modification example shown in FIG. 19, in a plan view, theplurality of overhang portions OH1, and the overhang portions OH2 andOH3 are formed to project from the main body portion BD only in thepositive direction of the X-axis direction, and the detecting electrodeRx has a comb-like shape.

In the fourth modification example shown in FIG. 20, in a plan view, theplurality of overhang portions OH1, and the overhang portions OH2 andOH3 are formed to project from the main body portion BD in the positivedirection or the negative direction of the X-axis direction, and thedetecting electrode Rx has a comb-like shape. In the fourth modificationexample, the detecting electrodes where the overhang portions OH1 to OH3project from the main body portion BD in the positive direction of theX-axis direction and the detecting electrodes where the overhangportions OH1 to OH3 project from the main body portion in the negativedirection of the X-axis direction are alternately arranged in the X-axisdirection.

In each case of the third modification example and the fourthmodification example, also, adjustment has been performed in the samemanner as the second embodiment such that the areas of the overhangportions OH2 and OH3 become larger than the area of the overhang portionOH1. Adjustment has been performed such that the area of a portion ofthe detecting electrode Rx overlapping with each of the drivingelectrodes Tx1 and Tx10 approaches the area of a portion of thedetecting electrode Rx overlapping with each of the driving electrodesTx2 to Tx9.

<Fifth Modification Example of Arrangement of Driving Electrodes andDetecting Electrodes>

FIG. 21 is a plan view schematically showing a fifth modificationexample of an arrangement of the driving electrodes and the detectingelectrodes in the touch panel provided in the display device of thesecond embodiment. FIG. 21 shows an example in which each of a pluralityof detecting electrodes has a plurality of main body portions. Notethat, in FIG. 21, illustration of the substrate 12, the display areaEA1, the detecting area EA2 and the area OEA (see FIG. 16) is omitted.Further, respective portions of the touch panel other than the detectingelectrodes Rx1 to Rx10, namely, the detecting electrodes Rx, in thefifth modification example are identical to respective portions of thetouch panel TP2 in the second embodiment. Therefore, the respectiveportions of the touch panel shown in FIG. 21 other than the detectingelectrodes Rx, which are members having the same functions as those ofmembers of the touch panel TP2 shown in FIG. 16 are denoted by the samereference numerals, and repetitive descriptions thereof will be omitted.

In the fifth modification example shown in FIG. 21, the detectingelectrode Rx includes three main body portions BD1, BD2 and BD3, aplurality of connecting portions CN1 and connecting portions CN2 andCN3, and a plurality of overhang portions OH1 and overhang portions OH2and OH3.

Each of the three main body portions BD1, BD2 and BD3 in the fifthmodification example can be made identical to each of the three mainbody portions BD1, BD2 and BD3 in the fourth modification example of thefirst embodiment. Note that, like the fourth modification example of thefirst embodiment, the present invention is not limited to the case inwhich the detecting electrode Rx includes three main body portions BD1,BD2 and BD3 and the detecting electrode Rx may include two, four or moremain body portions.

Each of the plurality of connecting portions CN1 in the fifthmodification example can be made identical to each of the plurality ofconnecting portions CN1 in the fourth modification example of the firstembodiment. Further, each of the plurality of overhang portions OH1 inthe fifth modification example can be made identical to each of theplurality of overhang portions OH1 in the fourth modification example ofthe first embodiment.

In a plan view, the connecting portion CN2 is formed inside an areaprovided with the driving electrode Tx1 so as to connect the main bodyportions BD1, BD2 and BD3. In a plan view, the connecting portion CN3 isformed inside an area provided with the driving electrode Tx10 so as toconnect the main body portions BD1, BD2 and BD3. The connecting portionsCN2 and CN3 are expanding portions for expanding the area of thedetecting electrode Rx as compared with the case in which the connectingportions are not formed.

In a plan view, the overhang portions OH2 are formed inside an areaprovided with the driving electrode Tx1 so as to project from the mainbody portion BD1 in the negative direction of the X-axis direction andproject from the main body portion BD3 in the positive direction of theX-axis direction. The overhang portions OH2 are expanding portions forexpanding the area of the detecting electrode Rx as compared with theoverhang portions OH2 are not formed.

In a plan view, the overhang portions OH3 are formed inside an areaprovided with the driving electrode Tx10 so as to project from the mainbody portion BD1 in the negative direction of the X-axis direction andproject from the main body portion BD3 in the positive direction of theX-axis direction. The overhang portions OH3 are expanding portions forexpanding the area of the detecting electrode Rx as compared with theoverhang portions OH3 are not formed.

In the fifth modification example, adjustment has been performed suchthat the respective areas of the connecting portion CN2 and the overhangportion OH2 become larger than the respective areas of the connectingportion CN1 and the overhang portion OH1. That is, adjustment has beenperformed in the same manner as the second embodiment such that the areaof a portion of the detecting electrode Rx overlapping with the drivingelectrode Tx1 approaches the area of a portion of the detectingelectrode Rx overlapping with each of the driving electrodes Tx2 to Tx9.

Furthermore, in the fifth modification example, adjustment has beenperformed such that the respective areas of the connecting portion CN3and the overhang portion OH3 become larger than the respective areas ofthe connecting portion CN1 and the overhang portion OH1. That is,adjustment has been performed in the same manner as the secondembodiment such that the area of a portion of the detecting electrode Rxoverlapping with the driving electrode Tx10 approaches the area of aportion of the detecting electrode Rx overlapping with each of thedriving electrodes Tx2 to Tx9.

<Sixth Modification Example of Arrangement of Driving Electrodes andDetecting Electrodes>

FIG. 22 is a plan view schematically showing a sixth modificationexample of arrangement of the driving electrodes and the detectingelectrodes in the touch panel provided in the display device of thesecond embodiment. FIG. 22 shows an example in which each of a pluralityof detecting electrodes has a plurality of main body portions. Notethat, in FIG. 22, illustration of the substrate 12, the display areaEA1, the detecting area EA2 and the area OEA (see FIG. 16) is omitted.Further, respective portions of the touch panel other than the detectingelectrodes Rx1 to Rx10, namely, the detecting electrodes Rx, in thesixth modification example are identical to respective portions of thetouch panel TP2 in the second embodiment. Therefore, members of thetouch panel shown in FIG. 22 other than the detecting electrodes Rx,which are members having the same functions as those of members of thetouch panel TP2 shown in FIG. 16 are denoted by the same referencenumerals, and repetitive descriptions thereof will be omitted.

In the sixth modification example shown in FIG. 22, the detectingelectrode Rx includes two main body portions BD1 and BD2, and connectingportions CN2 and CN3.

Each of the two main body portions BD1 and BD2 in the sixth modificationexample can be made identical to each of the two main body portions BD1and BD2 in the fifth modification example of the first embodiment. Notethat, the present invention is not limited to the case in which thedetecting electrode Rx includes two main body portions BD1 and BD2 butthe detecting electrode Rx may include three or more main body portionslike the fifth modification example of the first embodiment.

In a plan view, the connecting portion CN2 is formed inside an areaprovided with the driving electrode Tx1 so as to connect the main bodyportions BD1 and BD2. In a plan view, the connecting portion CN3 isformed inside an area provided with the driving electrode Tx10 so as toconnect the main body portions BD1 and BD2. The connecting portions CN2and CN3 are expanding portions for expanding the area of the detectingelectrode Rx as compared with a case in which the connecting portionsCN2 and CN3 are not formed.

On the other hand, as shown in FIG. 22, such a configuration can beadopted that the connecting portion or the overhang portion as theexpanding portion for expanding the area of the detecting electrode Rxis not formed inside an area provided with each of the drivingelectrodes Tx2 to Tx9 in a plan view.

In the sixth modification example, in the same manner as the secondembodiment, adjustment has been performed by forming the connectingportions CN2 and CN3 such that the area of a portion of the detectingelectrode Rx overlapping with each of the driving electrodes Tx1 andTx10 approaches the area of a portion of the detecting electrode Rxoverlapping with each of the driving electrodes Tx2 to Tx9.

<Electrostatic Capacitance Between Driving Electrode and DetectingElectrode>

Next, the electrostatic capacitance between the driving electrode andthe detecting electrode will be described with reference to firstcomparative example in the same manner as the first embodiment. Asdescribed above with reference to FIG. 13, the detecting electrode Rxincludes the main body BD and the overhang portions OH1 to OH3 in thefirst comparative example. In first comparative example, in a differentmanner from the second embodiment, the width WR2 of the overhang portionOH2 is equal to the width WR1 of the overhang portion OH1, and the widthWR3 of the overhang portion OH3 is equal to the width WR1 of theoverhang portion OH1.

In first comparative example, also, in the same manner as the secondembodiment, the width WD2 of the driving electrode Tx1 is smaller thanthe respective widths WD1 of the driving electrodes Tx2 to Tx9.Therefore, the area S2 of a portion of the detecting electrode Rxoverlapping with the driving electrode Tx1 becomes smaller than the areaS1 of a portion of the detecting electrode Rx overlapping with each ofthe driving electrodes Tx2 to Tx9. Further, the width WD3 of the drivingelectrode Tx10 is smaller than the respective widths WD1 of the drivingelectrodes Tx2 to Tx9. Therefore, the area S3 of a portion of thedetecting electrode Rx overlapping with driving electrode Tx10 becomessmaller than the area S1 of a portion of the detecting electrode Rxoverlapping with each of the driving electrodes Tx2 to Tx9. Therefore,the electrostatic capacitance between each of the driving electrodes Tx1and Tx10 and the detecting electrode Rx becomes smaller than each of thedriving electrodes Tx2 to Tx9 and the detecting electrode Rx.

Therefore, in the touch panel TP100 of the first comparative example, asdescribed above with reference to FIG. 14, a difference, namely, atolerance of the detected capacitance detected when a driving voltagehas been applied to each of the driving electrodes Tx1 and Tx10 to thelower limit LL1 of the ACD range becomes small, so that a noise immunityof the detected capacitance lowers. As a result, in the touch panelTP100 of the first comparative example, there is a possibility that theposition detection accuracies lower or the position detectionsensitivities lower on the driving electrodes Tx1 and Tx10 lower ascompared with on the driving electrodes Tx2 to Tx9.

<Main Feature and Advantageous Effect of this Embodiment>

In the second embodiment and the first modification example to the sixthmodification example thereof, in a plan view, the detecting electrode Rxis arranged in the area provided with the driving electrodes Tx1 andTx10, and the detecting electrode Rx includes, for example, the overhangportions OH2 and OH3, or the connecting portions CN2 and CN3 as theexpanding portions for expanding the area of the detecting electrode Rx.The overhang portions OH2 and OH3 will be described below on behalf ofthe overhang portions OH2 and OH3 or the connecting portions CN2 andCN3.

Adjustment has been performed such that the respective areas of theoverhang portions OH2 and OH3 become larger than the area of theoverhang portion OH1, and adjustment has been performed such that thearea of a portion of the detecting electrode Rx overlapping with each ofthe driving electrodes Tx1 and Tx10 approaches the area of a portion ofthe detecting electrode Rx overlapping with each of the drivingelectrodes Tx2 to Tx9. Therefore, adjustment can be performed such thatthe electrostatic capacitance between each of the driving electrodes Tx1and Tx10 and the detecting electrode Rx approaches the electrostaticcapacitance between each of the driving electrodes Tx1 and Tx10 and thedetecting electrode Rx. Therefore, the electrostatic capacitance betweeneach of the driving electrodes Tx1 and Tx10 and the detecting electrodeRx can be prevented or inhibited from becoming smaller than theelectrostatic capacitance between each of the driving electrodes Tx2 toTx9 and the detecting electrode Rx.

FIG. 15 described above is also a graph showing the detected capacitancedetected when a driving voltage has been applied to each of theplurality of driving electrodes in Example 3 and Example 4 which areexamples of the second embodiment. As shown in FIG. 15, in Example 3 andExample 4, also, it is assumed that the electrostatic capacitances,namely, the detected capacitances detected when a driving voltage hasbeen applied to the respective driving electrodes Tx2 to Tx9 take aconstant value CST1.

Here, respective areas of the overhang portions OH2 and OH3 arepreferably adjusted such that the electrostatic capacitances, namely,the detected capacitances detected when a driving voltage has beenapplied to the respective driving electrodes Tx1 and Tx10 fall withinthe range of ±10% to the constant value CST1. The case in which thedetecting electrode Rx includes the overhang portions OH2 and OH3 thusadjusted is shown as Example 3 shown in FIG. 15.

In Example 3 shown in FIG. 15, the differences, namely, the tolerancesof the detected capacitances detected when a driving voltage has beenapplied to the respective driving electrodes Tx1 and Tx10 to the lowerlimit LL1 of the ADC range can be inhibited from becoming small, ascompared with first comparative example shown in FIG. 14. A noiseimmunity of the detected capacitances detected when a driving voltagehas been applied to the respective driving electrodes Tx1 and Tx10 canbe inhibited from lowering. As a result, the position detectionaccuracies can be prevented or inhibited from lowering on the drivingelectrodes Tx1 and Tx10 and the position detection sensitivities can beprevented or inhibited from lowering thereon as compared with on thedriving electrodes Tx2 to Tx9. Therefore, the position detectionperformance in the display device can be improved.

Further, preferably, the respective areas of the overhang portions OH2and OH3 are adjusted such that the detected capacitances detected when adriving voltage has been applied to the respective driving electrodesTx1 and Tx10 become equal to the constant value CST1. The case in whichthe detecting electrode Rx includes the overhang portions OH2 and OH3thus adjusted is shown as Example 4 shown in FIG. 15.

In Example 4 shown in FIG. 15, the tolerances of the detectedcapacitances detected when a driving voltage has been applied to therespective driving electrodes Tx1 and Tx10 to the lower limit LL1 of theADC range can be inhibited from becoming small further securely ascompared with first comparative example shown in FIG. 14. The noiseimmunity of the detected capacitances detected when a driving voltagehas been applied to the respective driving electrodes Tx1 and Tx10 canbe inhibited from lowering further securely. As a result, the positiondetection accuracies can be prevented or inhibited from lowering furthersecurely on the driving electrodes Tx1 and Tx10 and the positiondetection sensitivities can be prevented or inhibited from loweringfurther securely thereon as compared with the on the driving electrodesTx2 to Tx9. Therefore, the position detection performance in the displaydevice can be improved.

(Third Embodiment)

In the second embodiment, adjustment has been performed such that thearea of a portion of the detecting electrode overlapping with thedriving electrode having a width smaller than those of the other drivingelectrodes becomes larger than the area of a portion of the detectingelectrode overlapping with each of the other driving electrodes in aplan view. On the other hand, in the third embodiment, adjustment hasbeen performed such that the area of a portion of the detectingelectrode overlapping with the driving electrode having a width largerthan those of the other driving electrodes becomes smaller than the areaof a portion of the detecting electrode overlapping with each of theother driving electrodes in a plan view.

Since respective portions of the display device of the third embodimentother than a touch panel TP3 are identical to the respective portions ofthe display device of the first embodiment other than the touch panelTP1, descriptions thereof are omitted.

<Arrangement of Driving Electrodes and Detecting Electrodes>

FIG. 23 is a plan view schematically showing an arrangement of drivingelectrodes and detecting electrodes in a touch panel provided in adisplay device of the third embodiment.

Note that, respective portions of the touch panel TP3 other than thedetecting electrodes Rx1 to Rx10, namely, the detecting electrodes Rx inthe third embodiment are identical to respective portions of the touchpanel TP1 in the first embodiment except for the widths WD1, WD2, andWD3 of the driving electrodes Tx1 to Tx10. Therefore, respectiveportions of the touch panel TP3 shown in FIG. 23 other than the drivingelectrodes Rx, having the same functions as those of the members of thetouch panel TP1 shown in FIG. 7 are denoted by the same referencenumerals, and descriptions thereof are omitted except for the widthsWD1, WD2, and WD3 of the driving electrodes Tx1 to Tx10. Note that, thedriving electrodes Tx1 to Tx10 are arranged inside the display area EA1in a section perpendicular to the X-axis direction.

In the third embodiment, the respective widths WD1 of the drivingelectrodes Tx2 to Tx9 are equal to one another in the same manner as thefirst embodiment. In the third embodiment, however, in a differentmanner from the first embodiment, the width WD2 of the driving electrodeTx1 is larger than the respective widths WD1 of the driving electrodesTx2 to Tx9 and the width WD3 of the driving electrode Tx10 is largerthan the respective widths WD1 of the driving electrodes Tx2 to Tx9.

As described above in the first embodiment, the respective widths WD1 ofthe driving electrodes Tx2 to Tx9 are an integral multiple of anarrangement period or a width of pixel electrodes, but since the numberof pixels in the Y-axis direction is determined according to aspecification required as the display device, such a case sometimesoccurs that the number of pixels in the Y-axis direction cannot bedivided by the number of pixels per one of the driving electrodes Tx. Insuch a case, a broken number which has occurred due to theindivisibility is allocated to, for example, the driving electrodes Txon both sides of an arrangement of the driving electrodes Tx in adivisional fashion, and the widths obtained by multiplying therespective allocated broken numbers by the arrangement period or thewidth of the pixel electrodes in the Y-axis direction are set as thewidths WD2 and DW3 of the driving electrodes Tx1 and Tx10, respectively.

However, when the allocated broken numbers are relatively small, such as1 or 2, it is sometimes difficult to set the widths obtained bymultiplying the allocated broken numbers by the arrangement period orthe width of the pixel electrodes in the Y-axis direction as the widthsWD2 and WD3 of the driving electrodes Tx1 and Tx10, respectively, forexample, in view of a manufacturing process. In such a case, the widthsobtained by multiplying the number of pixels obtained by adding theallocated numbers to the number of pixels per one driving electrode Txby the arrangement period or the width of the pixel electrodes in theY-axis direction are set as the widths WD2 and WD3 of the drivingelectrodes Tx1 and Tx10, respectively. Thus, the widths WD2 and WD3 ofthe driving electrodes Tx1 and Tx10 become larger than the respectivewidths WD1 of the driving electrodes Tx2 to Tx9.

For example, it is considered that 103 pixels are arranged in the Y-axisdirection and one driving electrode Tx is allocated to each 10 pixels.In this case, the remaining three pixels occurring by dividing 103pixels into respective groups of 10 pixels are divided into one pixeland two pixels, and the widths of the pixel electrodes corresponding tothe numbers of pixels obtained by adding the one pixel and the twopixels to the 10 pixels, respectively, are set as the widths of thedriving electrodes on both ends of the arrangement of the drivingelectrodes Tx. Therefore, for example, setting can be performed suchthat the respective widths WD1 of the driving electrodes Tx2 to Tx9 arewidths corresponding to 10 pixels, the width WD2 of the drivingelectrode Tx1 is a width corresponding to 11 pixels, and the width WD3of the driving electrode Tx10 is a width corresponding to 12 pixels.

In the third embodiment, in the same manner as the first embodiment, anintersection portion between each of the driving electrodes Tx2 to Tx9and the detecting electrode Rx is represented as CR1, an intersectionportion between the driving electrode Tx1 and the detecting electrode Rxis represented as CR2, and an intersection portion between the drivingelectrode Tx10 and the detecting electrode Rx is represented as CR3.Further, the electrostatic capacitance between each of the drivingelectrodes Tx2 to Tx9 and the detecting electrode Rx, namely, theelectrostatic capacitance formed at the intersection portion CR1, isrepresented as CP1. Further, the electrostatic capacitance between thedriving electrode Tx1 and the detecting electrode Rx, namely, theelectrostatic capacitance formed at the intersection portion CR2, isrepresented as CP2, and the electrostatic capacitance between thedriving electrode Tx10 and the detecting electrode Rx, namely, theelectrostatic capacitance formed at the intersection portion CR3, isrepresented as CP3. Here, an input position is detected based upon theelectrostatic capacitances CP1, CP2, and CP3.

The detecting electrode Rx includes a main body portion BD, and aplurality of overhang portions OH1 and overhang portions OH2 and OH3.The main body portion BD extends in the Y-axis direction, and the widthof the main body portion BD in the X-axis direction is represented asWB. Note that, in FIG. 23, the overhang portions OH1 formed inside anarea provided with the driving electrode Tx2, and the overhang portionsOH2 and OH3 are hatched.

Each of the plurality of overhang portions OH1 in the third embodimentcan be made identical with each of the plurality of overhang portionsOH1 in the first embodiment.

In a plan view, the overhang portions OH2 are formed inside an areaprovided with the driving electrode Tx1, namely inside the intersectionportion CR2 to overhang from the main body portion BD in the positivedirection and the negative direction of the X-axis direction,respectively. The overhang portion OH2 is an expanding portion forexpanding the area of the detecting electrode Rx as compared with thecase in which the overhang portion OH2 is not formed.

In a plan view, the overhang portions OH3 are formed inside an areaprovided with the driving electrode Tx10, namely inside the intersectionportion CR3 to overhang from the main body portion BD in the positivedirection and the negative direction of the X-axis direction,respectively. The overhang portion OH3 is an expanding portion forexpanding the area of the detecting electrode Rx as compared with thecase in which the overhang portion OH3 is not formed.

In the third embodiment, also, in the same manner as the firstembodiment, the area of a portion of the detecting electrode Rxoverlapping with each of the driving electrodes Tx2 to Tx9 isrepresented as S1, the area of a portion of the detecting electrode Rxoverlapping with the driving electrode Tx1 is represented as S2, and thearea of a portion of the detecting electrode Rx overlapping with thedriving electrode Tx10 is represented as S3. Here, the area of theoverhang portion OH2 has been adjusted such that the area S2 approachesthe area S1, and the area of the overhang portion OH3 has been adjustedsuch that the area S3 approaches the area S1. Further, preferably, thearea of the overhang portion OH2 has been adjusted such that the area S2becomes equal to the area S1 and the area of the overhang portion OH3has been adjusted such that the area S3 becomes equal to the area S1.

Note that, the expression “the area S2 approaches the area S1” meansthat the ratio of the area S2 to the area S1 approaches 1, and itpreferably means, for example, that the ratio of the area S2 to the areaS1 falls within the range of 0.9 to 1.1. Further, the expression “thearea S3 approaches the area S1” means that the ratio of the area S3 tothe area S1 approaches 1, and it preferably means, for example, that theratio of the area S3 to the area S1 falls within the range of 0.9 to1.1. That is, the expression “the second area approaches the first area”means that the ratio of the second area to the first area approaches 1,and it preferably means, for example, that the ratio of the second areato the first area falls within the range of 0.9 to 1.1 (the same goes tomodification examples of the third embodiment).

In the third embodiment, also, in the same manner as the firstembodiment, the length of the overhang portion OH1 in the X-axisdirection is represented as LN1, and the width of the overhang portionOH1 in the Y-axis direction is represented as WR1. Further, the lengthof the overhang portion OH2 in the X-axis direction is represented asLN2, and the width of the overhang portion OH2 in the Y-axis directionis represented as WR2. Further, the length of the overhang portion OH3in the X-axis direction is represented as LN3, and the width of theoverhang portion OH3 in the Y-axis direction is represented as WR3.

In the third embodiment, also, in the same manner as the firstembodiment, for example, it is assumed that the length LN1 of theoverhang portion OH1, the length LN2 of the overhang portion OH2, andthe length LN3 of the overhang portion OH3 are equal to each other.Here, adjustment has been performed such that the width WR2 of theoverhang portion OH2 is smaller than the width WR1 of the overhangportion OH1, and adjustment has been performed such that the width WR3of the overhang portion OH3 is smaller than the width WR1 of theoverhang portion OH1. That is, adjustment has been performed such thatthe area SO2 of the overhang portion OH2 which is a product of thelength LN2 and the width WR2 becomes smaller than the area SO1 of theoverhang portion OH1 which is a product of the length LN1 and the widthWR1. Adjustment has been performed such that the area SO3 of theoverhang portion OH3 which is a product of the length LN3 and the widthWR3 becomes smaller than the area SO1 of the overhang portion OH1 whichis a product of the length LN1 and the width WR1.

Furthermore, the area SB1 of the portion of the main body portion BDoverlapping with each of the driving electrodes Tx2 to Tx9 isrepresented by a product of the width WB and the width WD1. The area SB2of the portion of the main body portion BD overlapping with the drivingelectrode Tx1 is represented by a product of the width WB and the widthWD2, and the area SB3 of the portion of the main body portion BDoverlapping with the driving electrode Tx10 is represented by a productof the width WB and the width WD3. Therefore, the area S1 of the portionof the detecting electrode Rx overlapping with each of the drivingelectrodes Tx2 to Tx9 is represented by the above-mentioned Equation(1). The area S2 of the portion of the detecting electrode Rxoverlapping with the driving electrode Tx1 is represented by theabove-mentioned Equation (2), and the area S3 of the portion of thedetecting electrode Rx overlapping with the driving electrode Tx10 isrepresented by the above-mentioned Equation (3).

As described above, since the width WD2 is larger than the width WD1 andthe width WD3 is larger than WD1, the area SB2 is larger than the areaSB1 and the area SB3 is larger than SB1. Therefore, when the area SO2 ofthe overhang portion OH2 is equal to the area SO1 of the overhangportion OH1, the area S2 is larger than the area S1, so that theelectrostatic capacitance between the driving electrode Tx1 and thedetecting electrode Rx becomes larger than the electrostatic capacitancebetween each of the driving electrodes Tx2 to Tx9 and the detectingelectrode Rx. Further, when the area SO3 of the overhang portion OH3 isequal to the area SO1 of the overhang portion OH1, the area S3 is largerthan the area S1, so that the electrostatic capacitance between thedriving electrode Tx10 and the detecting electrode Rx becomes largerthan the electrostatic capacitance between each of the drivingelectrodes Tx2 to Tx9 and the detecting electrode Rx.

In the third embodiment, however, for example, since the width WR2 issmaller than the width WR1, adjustment has been performed that the areaSO2 of the overhang portion OH2 becomes smaller than the area SO1 of theoverhang portion OH1. Adjustment has been performed such that the areaS2 of the portion of the detecting electrode Rx overlapping with thedriving electrode Tx1 approaches the area S1 of the portion of thedetecting electrode Rx overlapping with each of the driving electrodesTx2 to Tx9. Therefore, adjustment can be performed such that theelectrostatic capacitance between the driving electrode Tx1 and thedetecting electrode Rx approaches the electrostatic capacitance betweeneach of the driving electrodes Tx2 to Tx9 and the detecting electrodeRx.

Further, in the third embodiment, for example, since the width WR3 issmaller than the width WR1, adjustment has been performed that the areaSO3 of the overhang portion OH3 becomes smaller than the area SO1 of theoverhang portion OHl. Adjustment has been performed such that the areaS3 of the portion of the detecting electrode Rx overlapping with thedriving electrode Tx10 approaches the area S1 of the portion of thedetecting electrode Rx overlapping with each of the driving electrodesTx2 to Tx9. Therefore, adjustment can be performed such that theelectrostatic capacitance between the driving electrode Tx10 and thedetecting electrode Rx approaches the electrostatic capacitance betweeneach of the driving electrodes Tx2 to Tx9 and the detecting electrodeRx.

That is, in the third embodiment, adjustment has been performed suchthat the area of a portion of the detecting electrode overlapping withthe driving electrode having a width larger than those of the otherdriving electrodes approaches the area of the portion of the detectingelectrode overlapping with each of the other driving electrodes in aplan view.

Further, in the third embodiment, when the driving electrodes having awidth larger than those of the other driving electrodes are arranged onboth sides of the arrangement of the other driving electrodes,adjustment can be performed such that the electrostatic capacitancebetween the driving electrode having the larger width and the detectingelectrode approaches the electrostatic capacitance between each of theother driving electrodes and the detecting electrode.

Further, in the third embodiment, in order to adjust the electrostaticcapacitance between the driving electrode having the width larger thanthose of the other driving electrodes and the detecting electrode, theexpanding portion for expanding the area of the detecting electrode isprovided inside the display area in a plan view.

<First Modification Example of Arrangement of Driving Electrodes andDetecting Electrodes>

FIG. 24 is a plan view schematically showing a first modificationexample of arrangement of the driving electrodes and the detectingelectrodes in the touch panel provided in the display device of thethird embodiment. FIG. 24 shows an example in which the width of thedriving electrode Tx1 is larger than the respective widths of thedriving electrodes Tx2 to Tx9 but the width of the driving electrodeTx10 is equal to the respective widths of the driving electrodes Tx2 toTx9. Note that, members of the touch panel TP3 shown in FIG. 24 havingthe same functions as those of the members of the touch panel TP3 shownin FIG. 23 are denoted by the same reference numerals and descriptionsthereof are omitted.

In the first modification example, the respective widths WD1 of thedriving electrodes Tx2 to Tx10 are equal to one another and the widthWD2 of the driving electrode Tx1 is larger than the respective widthsWD1 of the driving electrodes Tx2 to Tx10.

The detecting electrode Rx includes the main body portion BD, and theplurality of overhang portions OH1 and the overhang portions OH2, but itdoes not include the overhang portions OH3 (see FIG. 23). That is, theoverhang portions OH1 are formed inside an area provided with thedriving electrode Tx10.

Each of the plurality of overhang portions OH1 in the first modificationexample can be made identical to each of the plurality of overhangportions OH1 in the third embodiment. Further, the overhang portion OH2in the first modification example can be made identical to the overhangportion OH2 in the third embodiment.

In the first modification example, like the third embodiment, adjustmenthas been performed such that the area of the overhang portion OH2becomes smaller than the area of the overhang portion OH1, andadjustment has been performed such that the area of a portion of thedetecting electrode Rx overlapping with the driving electrode Tx1approaches the area of a portion of the detecting electrode Rxoverlapping with each of the driving electrodes Tx2 to Tx10. Therefore,adjustment can be performed such that the electrostatic capacitancebetween the driving electrode Tx1 and the detecting electrode Rxapproaches the electrostatic capacitance between each of the drivingelectrodes Tx2 to Tx10 and the detecting electrode Rx.

That is, even when the driving electrode having a width larger thanthose of the other driving electrodes is arranged only outside one sideof the arrangement of the other driving electrodes, adjustment can beperformed such that the electrostatic capacitance between the drivingelectrode having the larger width and the detecting electrode approachesthe electrostatic capacitance between each of the other drivingelectrodes and the detecting electrode.

<Second Modification Example of Arrangement of Driving Electrodes andDetecting Electrodes>

FIG. 25 is a plan view schematically showing a second modificationexample of an arrangement of driving electrodes and detecting electrodesin the touch panel provided in the display device of the thirdembodiment. FIG. 25 shows an example in which the driving electrodehaving a width larger than those of the other driving electrodes is notarranged outside the arrangement of the other driving electrodes but itis arranged in the middle of arrangement of the other drivingelectrodes. Note that, members of the touch panel TP3 shown in FIG. 25having the same functions as those of the members of the touch panel TP3shown in FIG. 23 are denoted by the same reference numerals anddescriptions thereof are omitted.

In the second modification example, in a plan view, the respectivewidths of the driving electrodes Tx1 to Tx3 and Tx5 to Tx10 in theY-axis direction are represented as WD1 and the width, in the Y-axisdirection, of the driving electrode Tx4 arranged in the middle of thearrangement of the driving electrodes is represented as WD2. Here, therespective widths WD1 of the driving electrodes Tx1 to Tx3 and Tx5 toTx10 are equal to one another, and the width WD2 of the drivingelectrode Tx4 is larger than the respective widths WD1 of the drivingelectrodes Tx1 to Tx3 and Tx5 to Tx10.

For example, according to a specification required as a display deviceor the like, a driving electrode having a width obtained by multiplyingthe number of pixels obtained by adding a broken number which hasoccurred due to the indivisibility of the number of pixels in the Y-axisdirection to the number of pixels per one driving electrode Tx by thearrangement period or the width of pixel electrodes may not be arrangedoutside the arrangement of the driving electrodes but it may be arrangedin the middle of the arrangement of the driving electrodes. In such acase, for example, the width WD2 of the driving electrode Tx4 which isthe driving electrode arranged in the middle of the arrangement of thedriving electrodes is made larger than the respective widths WD1 of thedriving electrodes Tx1 to Tx3 and Tx5 to Tx10 which are the otherdriving electrodes.

Note that, the widths WD1 may also be made different between the drivingelectrodes Tx1 to Tx3 and the driving electrodes Tx5 to Tx10. Further,in the second modification example, the example in which the drivingelectrode having a width larger than those of the other drivingelectrodes is arranged at the fourth position in the arrangement of thedriving electrodes is described, but the position of the drivingelectrode having the larger width is not limited to the fourth positionbut it may be any position in the middle portion of the arrangement.

In the second modification example, the intersection portion betweeneach of the driving electrodes Tx1 to Tx3 and Tx5 to Tx10 and thedetecting electrode Rx is represented as CR1, and the intersectionportion between the driving electrode Tx4 and the detecting electrode Rxis represented as CR2. Further, the electrostatic capacitance betweeneach of the driving electrodes Tx1 to Tx3 and Tx5 to Tx10 and thedetecting electrode Rx is represented as CP1, and the electrostaticcapacitance between the driving electrode Tx4 and the detectingelectrode Rx is represented as CP2. Here, an input position is detectedbased upon the electrostatic capacitances CP1 and CP2.

Each of the plurality of overhang portions OH1 in the secondmodification example can be made equal to each of the plurality ofoverhang portions OH1 in the third embodiment. Furthermore, the overhangportion OH2 in the second modification example may be made equal to theoverhang portion OH2 in the third embodiment.

In the second modification example, also, adjustment has been performedlike the third embodiment such that the area of the overhang portion OH2becomes smaller than the area of the overhang portion OH1. Adjustmenthas been performed such that the area of a portion of the detectingelectrode Rx overlapping with the driving electrode Tx4 approaches thearea of a portion of the detecting electrode Rx overlapping with each ofthe driving electrodes Tx1 to Tx3 and Tx5 to Tx10.

<Third Modification Example of Arrangement of Driving Electrodes andDetecting Electrodes>

FIG. 26 is a plan view schematically showing a third modificationexample of arrangement of driving electrodes and detecting electrodes inthe touch panel provided in the display device of the third embodiment.FIG. 26 shows an example in which the overhang portions OH1 to OH3project to one side of the main body portion BD, but they do not projectto the other side of the main body portion BD. Note that, respectiveportions of the touch panels TP3 other than the overhang portions OH1 toOH3 in the third modification example are identical to the respectiveportion in the touch panel TP3 in the third embodiment. Therefore,respective portions of the touch panels TP3 shown in FIG. 26 other thanthe overhang portions OH1 to OH3, which are members having the samefunctions as those of members of the touch panel TP3 shown in FIG. 23are denoted by the same reference numerals, and repetitive descriptionsthereof will be omitted.

In the third modification example shown in FIG. 26, in a plan view, theplurality of overhang portions OH1, and the overhang portions OH2 andOH3 are formed to project from the main body portion BD only in thepositive direction of the X-axis direction, and the detecting electrodeRx has a comb-like shape.

In the third modification example, also, in the same manner as the thirdembodiment, adjustment has been performed such that the areas of theoverhang portions OH2 and OH3 are smaller than the area of the overhangportion OH1. Adjustment has been performed such that the area of aportion of the detecting electrode Rx overlapping with each of thedriving electrodes Tx1 and Tx10 approaches the area of a portion of thedetecting electrode Rx overlapping with each of the driving electrodesTx2 to Tx9.

Note that, in the third modification example, also, in the same manneras the fourth modification example of the second embodiment shown inFIG. 20, the plurality of overhang portions OH1 and the overhangportions OH2 and OH3 may be formed so as to project from the main bodyportion BD in the positive direction or the negative direction of theX-axis direction. The detecting electrodes where the overhang portionsOH1 to OH3 project from the main body portion BD in the positivedirection of the X-axis direction and the detecting electrodes where theoverhang portions OH1 to OH3 project from the main body portion BD inthe negative direction of the X-axis direction are alternately arrangedin the X-axis direction.

<Fourth Modification Example of Arrangement of Driving Electrodes andDetecting Electrodes>

FIG. 27 is a plan view schematically showing a fourth modificationexample of an arrangement of driving electrodes and detecting electrodesin the touch panel provided in the display device of the thirdembodiment. FIG. 27 shows an example in which each of a plurality ofdetecting electrodes has a plurality of main body portions. Note that,in FIG. 27, illustration of the substrate 12, the display area EA1, thedetecting area EA2 and the area OEA (see FIG. 23) is omitted. Further,respective portions of the touch panel other than the detectingelectrodes Rx1 to Rx10, namely, the detecting electrodes Rx, in thefourth modification example are identical to the respective portions ofthe touch panel TP3 in the third embodiment. Therefore, the respectiveportions of the touch panel shown in FIG. 27 other than the detectingelectrodes Rx, which are members having the same functions as those ofmembers of the touch panel TP3 shown in FIG. 23 are denoted by the samereference numerals, and repetitive descriptions thereof will be omitted.

In the fourth modification example shown in FIG. 27, the detectingelectrode Rx includes three main body portions BD1, BD2 and BD3, aplurality of connecting portions CN1 and connecting portions CN2 andCN3, and a plurality of overhang portions OH1 and overhang portions OH2and OH3.

The three main body portions BD1, BD2 and BD3 in the fourth modificationexample can be made identical to the three main body portions BD1, BD2and BD3 in the fourth modification example of the first embodiment,respectively. Note that, like the fourth modification example of thefirst embodiment, the present invention is not limited to the case inwhich the detecting electrode Rx includes three main body portions BD1,BD2 and BD3 and the detecting electrode Rx may include two, four or moremain body portions.

The plurality of connecting portions CN1 in the fourth modificationexample can be made identical to the plurality of connecting portionsCN1 in the fourth modification example of the first embodiment,respectively. Further, the plurality of overhang portions OH1 in thefifth modification example can be made identical to the plurality ofoverhang portions OH1 in the fourth modification example of the firstembodiment, respectively.

In a plan view, the connecting portion CN2 is formed inside an areaprovided with the driving electrode Tx1 so as to connect the main bodyportions BD1, BD2 and BD3. In a plan view, the connecting portion CN3 isformed inside an area provided with the driving electrode Tx10 so as toconnect the main body portions BD1, BD2 and BD3. The connecting portionsCN2 and CN3 are expanding portions for expanding the area of thedetecting electrode Rx as compared with the case in which the connectingportions CN2 and CN3 are not formed.

In a plan view, the overhang portions OH2 are formed inside an areaprovided with the driving electrode Tx1 so as to project from the mainbody portion BD1 in the negative direction of the X-axis direction andproject from the main body portion BD3 in the positive direction of theX-axis direction. The overhang portion OH2 is expanding portions forexpanding the area of the detecting electrode Rx as compared with theoverhang portion OH2 is not formed.

In a plan view, the overhang portions OH3 are formed inside an areaprovided with the driving electrode Tx10 so as to project from the mainbody portion BD1 in the negative direction of the X-axis direction andproject from the main body portion BD3 in the positive direction of theX-axis direction. The overhang portion OH3 is an expanding portions forexpanding the area of the detecting electrode Rx as compared with theoverhang portion OH3 is not formed.

In the fourth modification example, adjustment has been performed suchthat the respective areas of the connecting portion CN2 and the overhangportion OH2 become smaller than the respective areas of the connectingportion CN1 and the overhang portion OH1. That is, adjustment has beenperformed like the third embodiment such that the area of a portion ofthe detecting electrode Rx overlapping with the driving electrode Tx1approaches the area of a portion of the detecting electrode Rxoverlapping with each of the driving electrodes Tx2 to Tx9.

Furthermore, in the fourth modification example, adjustment has beenperformed such that the respective areas of the connecting portion CN3and the overhang portion OH3 become smaller than the respective areas ofthe connecting portion CN1 and the overhang portion OH1. That is, likethe third embodiment, adjustment has been performed such that the areaof a portion of the detecting electrode Rx overlapping with the drivingelectrode Tx10 approaches the area of a portion of the detectingelectrode Rx overlapping with each of the driving electrodes Tx2 to Tx9.

<Fifth Modification Example of Arrangement of Driving Electrodes andDetecting Electrodes>

FIG. 28 is a plan view schematically showing a fifth modificationexample of an arrangement of driving electrodes and detecting electrodesin the touch panel provided in the display device of the thirdembodiment. FIG. 28 shows an example in which each of a plurality ofdetecting electrodes has a plurality of main body portions. Note that,in FIG. 28, illustration of the substrate 12, the display area EA1, thedetecting area EA2 and the area OEA (see FIG. 23) is omitted. Further,respective portions of the touch panel other than the detectingelectrodes Rx1 to Rx10, namely, the detecting electrodes Rx, in thefifth modification example are identical to the respective portions ofthe touch panel TP3 in the third embodiment. Therefore, the respectiveportions of the touch panel shown in FIG. 28 other than the detectingelectrodes Rx, which are members having the same functions as members ofthe touch panel TP3 shown in FIG. 23 are denoted by the same referencenumerals, and repetitive descriptions thereof will be omitted.

In the fifth modification example shown in FIG. 28, the detectingelectrode Rx includes two main body portions BD1 and BD2, and connectingportions CN1.

The two main body portions BD1 and BD2 in the fifth modification examplecan be made identical to the two main body portions BD1 and BD2 in thefifth modification example of the first embodiment, respectively. Notethat, like the fifth modification example of the first embodiment, thepresent invention is not limited to the case in which the detectingelectrode Rx includes two main body portions BD1 and BD2, and thedetecting electrode Rx may include three or more main body portions.

In a plan view, the connecting portion CN1 is formed inside an areaprovided with each of the driving electrodes Tx2 to Tx9 so as to connectthe main body portions BD1 and BD2. The connecting portion CN1 is anexpanding portion for expanding the area of the detecting electrode Rxas compared with the case in which the connecting portion CN1 is notformed.

On the other hand, as shown in FIG. 28, such a configuration can beadopted that the connecting portion or the overhang portion as theexpanding portion for expanding the area of the detecting electrode Rxis not formed inside an area provided with each of the drivingelectrodes Tx2 and Tx10 in a plan view.

In the fifth modification example, like the third embodiment, adjustmenthas been performed by forming the connecting portion CN1 such that thearea of a portion of the detecting electrode Rx overlapping with each ofthe driving electrodes Tx1 and Tx10 approaches the area of a portion ofthe detecting electrode Rx overlapping with each of the drivingelectrodes Tx2 to Tx9.

Note that, in the fifth modification example, also, like the secondmodification example of the third embodiment, the driving electrodehaving a width larger than the widths of the other driving electrodes isnot arranged outside the arrangement of the driving electrodes but itmay be arranged in the middle of the arrangement of the drivingelectrodes.

<Sixth Modification Example of Arrangement of Driving Electrodes andDetecting Electrodes>

FIG. 29 is a plan view schematically showing a sixth modificationexample of an arrangement of driving electrodes and detecting electrodesin the touch panel provided in the display device of the thirdembodiment. FIG. 29 shows an example in which the length of the overhangportion has been adjusted instead of the width of the overhang portion.Note that, members of the touch panel TP3 shown in FIG. 29, having thesame functions as those of members of the touch panel TP3 shown in FIG.23 are denoted by the same reference numerals, and repetitivedescriptions thereof will be omitted.

In the sixth modification example shown in FIG. 29, the drivingdetecting electrode Rx includes a main body portion BD, a plurality ofoverhang portions OH1, and overhang portions OH2 and OH3. The main bodyportion BD extends in the Y-axis direction, and the width of the mainbody portion BD in the X-axis direction is represented as WB. Note that,in FIG. 29, the overhang portion OH1 formed inside an area provided withthe driving electrode Tx2, and the overhang portions OH2 and OH3 arehatched.

The plurality of overhang portions OH1 in the sixth modification examplemay be made equal to the plurality of overhang portions OH1 in the thirdembodiment, respectively.

In a plan view, the overhang portions OH2 are formed inside an areaprovided with the driving electrode Tx1, namely, inside the intersectionportion CR2, so as to project from the main body portion BD in thepositive direction and the negative direction of the X-axis direction,respectively. The overhang portion OH2 is an expanding portion forexpanding the area of the detecting electrode Rx as compared with theoverhang portion OH2 is not formed.

In a plan view, the overhang portions OH3 are formed inside an areaprovided with the driving electrode Tx10, namely, inside theintersection portion CR3, so as to project from the main body portion BDin the positive direction and the negative direction of the X-axisdirection, respectively. The overhang portion OH3 is an expandingportions for expanding the area of the detecting electrode Rx ascompared with the overhang portion OH3 is not formed.

In the sixth modification example, in a different manner from the thirdembodiment, for example, it is assumed that the width WR1 of theoverhang portion OH1, the width WR2 of the overhang portion OH2, and thewidth WR3 of the overhang portion OH3 are made equal to one another.Here, for example, adjustment has been performed such that the lengthLN2 of the overhang portion OH2 becomes smaller than the length LN1 ofthe overhang portion OH1, and adjustment has been performed such thatthe length LN3 of the overhang portion OH3 becomes smaller than thelength LN1 of the overhang portion OH1.

In the sixth modification example, for example, adjustment has beenperformed by making the length LN2 shorter than the length LN1 such thatthe area of the overhang portion OH2 becomes smaller than the area ofthe overhang portion OH1 Like the third embodiment, adjustment has beenperformed such that the area of a portion of the detecting electrode Rxoverlapping with the driving electrode Tx1 approaches the area of aportion of the detecting electrode Rx overlapping with each of thedriving electrodes Tx2 to Tx9.

Further, in the sixth modification example, for example, adjustment hasbeen performed by making the length LN3 shorter than the length LN1 suchthat the area of the overhang portion OH3 becomes smaller than the areaof the overhang portion OH1. Like the third embodiment, adjustment hasbeen performed such that the area of a portion of the detectingelectrode Rx overlapping with the driving electrode Tx10 approaches thearea of a portion of the detecting electrode Rx overlapping with each ofthe driving electrodes Tx2 to Tx9.

<Regarding Electrostatic Capacitance between Driving Electrode andDetecting Electrode>

Next, the electrostatic capacitance between the driving electrode andthe detecting electrode will be described with reference to secondcomparative example.

FIG. 30 is a plan view schematically showing an arrangement of drivingelectrodes and detecting electrodes in a touch panel provided in adisplay device of a second comparative example.

In second comparative example, it is assumed that the detectingelectrode Rx includes a main body portion BD and overhang portions OH1to OH3, but the area of the overhang portion OH1, the area of theoverhang portion OH2, and the area of the overhang portion OH3 are equalto one another. It is assumed that the main body portion BD extends inthe Y-axis direction, and the width of the main body portion BD in theX-axis direction is represented as WB.

FIG. 31 is a graph showing a detected capacitance detected when adriving voltage has been applied to each of the plurality of drivingelectrodes in the second comparative example. In FIG. 31, a horizontalaxis represents a driving electrode applied with a driving voltage and avertical axis represents a detected capacitance like FIG. 14. Further,in FIG. 31, a range of a detected capacitance which can be detected bythe ADC, namely, a lower limit LL1 and an upper limit UL1 of the ADCrange is shown like FIG. 14. Further, the detected capacitance shown inFIG. 31 is equal to the electrostatic capacitance between each of thedriving electrodes Tx1 to Tx10 and the detecting electrode Rx like thedetected capacitance shown in FIG. 14.

Note that, respective potions of the touch panel TP200 of the secondcomparative example shown in FIG. 30 other than the detecting electrodesRx1 to Rx10, namely, the detecting electrode Rx are identical to therespective portions of the touch panel TP3 of the third embodiment shownin FIG. 23 other than the detecting electrode Rx. Further, respectiveportions of the display device provided with the touch panel TP200 ofthe second comparative example other than the touch panel TP200 areidentical to the respective portions of the display device LCD1 shown inFIG. 6 other than the touch panel TP1.

That is, in the second comparative example, also, the width WD2 of thedriving electrode Tx1 is larger than the respective widths WD1 of thedriving electrodes Tx2 to Tx9 and the width WD3 of the driving electrodeTx10 is larger than the respective widths WD1 of the driving electrodesTx2 to Tx9 like the third embodiment.

Further, respective portions of the detecting electrode Rx in the secondcomparative example are identical to the respective portions of thedetecting electrode Rx in the third embodiment except that the area ofthe overhang portion OH1, the area of the overhang portion OH2, and thearea of the overhang portion OH3 are equal to one another.

Note that, in FIG. 30, the overhang portions OH1 formed inside an areaprovided with the driving electrode Tx2, and the overhang portions OH2and OH3 are hatched.

In second comparative example, also, like the third embodiment, thewidth WD2 of the driving electrode Tx1 is larger than the respectivewidths WD1 of the driving electrodes Tx2 to Tx9. Therefore, the area S2of a portion of the detecting electrode Rx overlapping with the drivingelectrode Tx1 becomes larger than the area S1 of a portion of thedetecting electrode Rx overlapping with each of the driving electrodesTx2 to Tx9. Further, also, the width WD3 of the driving electrode Tx10is larger than the respective widths WD1 of the driving electrodes Tx2to Tx9. Therefore, the area S3 of a portion of the detecting electrodeRx overlapping with the driving electrode Tx10 becomes larger than thearea S1 of a portion of the detecting electrode Rx overlapping with eachof the driving electrodes Tx2 to Tx9. Accordingly, the electrostaticcapacitance between each of the driving electrodes Tx1 and Tx10 and thedetecting electrode Rx becomes larger than the electrostatic capacitancebetween each of the driving electrodes Tx2 to Tx9 and the detectingelectrode Rx.

In the touch panel TP200 of the second comparative example, as shown inFIG. 31, the electrostatic capacitances, namely, the detectedcapacitances detected when a driving voltage has been applied to thedriving electrodes Tx2 to Tx9, respectively, become a constant valueCST1.

In the touch panel TP200 of the second comparative example, however, theelectrostatic capacitance, namely, the detected capacitance detectedwhen a driving voltage has been applied to each of the drivingelectrodes Tx1 and Tx10 become larger than the constant value CST1. Whenthe detected capacitance becomes larger than the constant value CST1,there is such a possibility that the detected capacitance approaches theupper limit UL1 or becomes larger than the upper limit UL1. That is, adifference, namely, a tolerance of the detected capacitance detectedwhen the driving voltage has been applied to each of the drivingelectrodes Tx1 and Tx10 to the upper limit UL1 of the ADC range becomessmall, so that a noise immunity of the detected capacitance lowers. As aresult, in the touch panel TP200 of the second comparative example,position detection accuracies may lower or the position detectionsensitivities may lower on the driving electrodes Tx1 and Tx10 ascompared with on the driving electrodes Tx2 to Tx9.

<Main Feature and Advantageous Effect of This Embodiment>

In the third embodiment and the first modification example to the sixthmodification example thereof, in a plan view, the detecting electrode Rxis arranged in the area provided with the driving electrodes Tx1 andTx10, respective, and they include, for example, the overhang portionsOH2 and OH3, the connecting portions CN2 and CN3, or the connectingportion CN1 as the expanding portions for expanding the area of thedetecting electrode Rx. In the following, the overhang portions OH2 andOH3 will be described on behalf of the overhang portions OH2 and OH3,the connecting portions CN2 and CN3, or the connecting portion CN1.

Adjustment has been performed such that the respective areas of theoverhang portions OH2 and OH3 become smaller than the area of theoverhang portion OH1, and adjustment has been performed such that thearea of a portion of the detecting electrode Rx overlapping with each ofthe driving electrodes Tx1 and Tx10 approaches the area of a portion ofthe detecting electrode Rx overlapping with each of the drivingelectrodes Tx2 to Tx9. Therefore, adjustment can be performed such thatthe electrostatic capacitance between each of the driving electrodes Tx1and Tx10 and the detecting electrode Rx approaches the electrostaticcapacitance between each of the driving electrodes Tx1 and Tx10 and thedetecting electrode Rx. Therefore, the electrostatic capacitance betweeneach of the driving electrodes Tx1 and Tx10 and the detecting electrodeRx can be prevented or inhibited from becoming larger than theelectrostatic capacitance between each of the driving electrodes Tx2 toTx9 and the detecting electrode Rx.

FIG. 32 is a graph showing the detected capacitance detected when adriving voltage has been applied to each of the plurality of drivingelectrodes in Example 5 and Example 6 which are examples of the thirdembodiment. In FIG. 32, a horizontal axis represents a driving electrodeapplied with a driving voltage and a vertical axis represents a detectedcapacitance like FIG. 15. Further, in FIG. 32, a range of a detectedcapacitance which can be detected by the ADC, namely, a lower limit LL1and an upper limit UL1 of the ADC range is shown like FIG. 15. Further,the detected capacitance shown in FIG. 32 is equal to the electrostaticcapacitance between each of the driving electrodes Tx1 to Tx10 and thedetecting electrode Rx in the same manner as the detected capacitanceshown in FIG. 15.

As shown in FIG. 32, in Example 5 and Example 6, also, it is assumedthat the electrostatic capacitance, namely, the detected capacitancedetected when a driving voltage has been applied to each of the drivingelectrodes Tx2 to Tx9 takes a constant value CST1.

Here, respective areas of the overhang portions OH2 and OH3 arepreferably adjusted such that the electrostatic capacitance, namely, thedetected capacitance detected when a driving voltage has been applied toeach of the driving electrodes Tx1 and Tx10 falls within the range of±10% to the constant value CST1. The case in which the detectingelectrode Rx includes the overhang portions OH2 and OH3 thus adjusted isshown as Example 5 shown in FIG. 32.

In Example 5 shown in FIG. 32, the difference, namely, the tolerance ofthe detected capacitance detected when a driving voltage has beenapplied to each of the driving electrodes Tx1 and Tx10 to the upperlimit UL1 of the ADC range can be inhibited from becoming small, ascompared with second comparative example shown in FIG. 31. A noiseimmunity of the detected capacitance detected when a driving voltage hasbeen applied to each of the driving electrodes Tx1 and Tx10 can beinhibited from lowering. As a result, the position detection accuraciescan be prevented or inhibited from lowering on the driving electrodesTx1 and Tx10 and the position detection sensitivities can be preventedor inhibited from lowering thereon as compared with on the drivingelectrodes Tx2 to Tx9. Therefore, the position detection performance inthe display device can be improved.

Further, preferably, the respective areas of the overhang portions OH2and OH3 are adjusted such that the detected capacitance detected when adriving voltage has been applied to each of the driving electrodes Tx1and Tx10 becomes equal to the constant value CST1. The case in which thedetecting electrode Rx includes the overhang portions OH2 and OH3 thusadjusted is shown as Example 6 shown in FIG. 32.

In Example 6 shown in FIG. 32, the tolerance of the detected capacitancedetected when a driving voltage has been applied to each of the drivingelectrodes Tx1 and Tx10 to the upper limit UL1 of the ADC range can beinhibited from becoming small further securely as compared with secondcomparative example shown in FIG. 31. The noise immunity of the detectedcapacitance detected when a driving voltage has been applied to each ofthe driving electrodes Tx1 and Tx10 can be inhibited from loweringfurther securely. As a result, the position detection accuracies can beprevented or inhibited from lowering on the driving electrodes Tx1 andTx10 and the position detection sensitivities can be prevented orinhibited from lowering thereon as compared with the on the drivingelectrodes Tx2 to Tx9. Therefore, the position detection performance inthe display device can be improved.

(Fourth Embodiment)

In the first embodiment to the third embodiment, the example in whichthe touch panel as the input device including the driving electrodehaving a width different from those of the other driving electrodes hasbeen applied to the input device provided in the liquid crystal displaydevice of an in-cell type has been described. On the other hand, in thefourth embodiment, an example in which the touch panel as the inputdevice including the driving electrode having a width different fromthose of the other driving electrodes has been applied to an inputdevice as a single body or an input device provided in a display deviceof an on-cell type will be described.

Note that, the touch panel of the fourth embodiment can be applied to aninput device provided in a display device of an on-cell type such as aninput device provided on various display devices such as an organic ELdisplay device including liquid crystal display device.

<Configuration of Touch Panel>

Next, a configuration of the touch panel of the fourth embodiment willbe described.

FIG. 33 is a plan view showing a configuration of one example of thetouch panel of the fourth embodiment. FIG. 34 is a cross-sectional viewshowing a configuration of the one example of the touch panel of thefourth embodiment. FIG. 34 is a cross-sectional view taken along theline A-A in FIG. 33.

As shown in FIG. 33, a touch panel TP4 has a substrate 12 c. Thesubstrate 12 c has a front surface 12 d and a rear surface 12 epositioned on the opposite side of the front surface 12 d.

Note that, in the fourth embodiment, the term “plan view” means the casein which the display device has been viewed in a direction perpendicularto the front surface 12 d of the substrate 12 c.

A plurality of driving electrodes Tx is formed on the rear surface 12 eof the substrate 12 c. The plurality of driving electrodes Tx iscomposed of a transparent conductive film having translucency, namely, atransparent conductive film, for example, ITO or the like. As shown inFIG. 33, the plurality of driving electrodes Tx is provided side by sideso as to extend in one direction inside the detection area EA2 which isan area where the touch panel detects a position. Here, the drivingelectrodes Tx are arranged inside the detection area EA2 in a sectiontaken along the line A-A. On the other hand, as shown in FIG. 33, thedriving electrodes Tx may be formed such that both ends thereof extendoutside the detection area EA2.

Furthermore, in the fourth embodiment, even if the touch panel isprovided in a display device, the display device is a display device ofan on-cell type. Therefore, the detection area EA2 which is an areawhere the touch panel detects a position is not required to coincidewith the display area EA1 (see FIG. 4) which is an area where thedisplay device performs displaying.

A plurality of detecting electrodes Rx is formed on the front surface 12d of the substrate 12 c. The plurality of detecting electrodes Rx arecomposed of a transparent conductive film having translucency, namely, atransparent conductive film, for example, ITO or the like.

A wiring board 21 c is formed on the rear surface 12 e of the substrate12 c. The wiring board 21 c may be, for example, a so-called flexiblewiring board like the wiring board 21 of the first embodiment. Wirings21 b are formed in the wiring board 21 c. One end of the wiring 21 b iselectrically connected to a plurality of driving electrodes Tx,respectively, and the other end thereof is electrically connected to adriving circuit DT1. The driving circuit DR1 applies, to the drivingelectrodes Tx, the driving waveform DW for input position detectionexplained with reference to FIG. 2.

A wiring board 22 is formed on the front surface 12 d of the substrate12 c. The wiring board 22 may be, for example, a so-called flexiblewiring board in the same manner as the first embodiment. Wirings 22 aare formed on the wiring board 22. One end of the wiring 22 a iselectrically connected to the plurality of detecting electrodes Rx,respectively, and the other end thereof is electrically connected to adetecting circuit DT1. The detecting circuit DT1 detects an inputposition based upon a detection signal.

<Configuration of Display Device>

FIG. 35 is a cross-sectional view showing a configuration of one exampleof the display device of the fourth embodiment. The display device shownin FIG. 35 is a display device with a touch detection function of anon-cell type configured by attaching the touch panel TP4 on the frontsurface 12 a of the substrate 12 of a display device LCD2 which is thedisplay device composed of the liquid crystal display device describedabove with reference to FIG. 6 from which the detecting electrodes Rxand the wirings 21 b, and the driving circuit DR1 have been removed.Therefore, respective portions of the display device LCD2 are identicalto those of the display device LCD1 shown in FIG. 6, from which thedetecting electrodes Rx and the wirings 21 b, and the driving circuitDR1 have been removed, the descriptions thereof are omitted.

Here, the common electrodes 14 provided in the display device LCD2 arenot used as detecting electrodes of the touch panel. Further, in thedisplay device LCD2 as the liquid crystal display device, for example,the TN (Twisted Nematic) mode or the VA (Vertical Alignment) mode can beused as the vertical-electric-field mode of the system for applyingelectric field in order to change arrangement of liquid crystalmolecules in a liquid crystal layer. Further, the above-described IPSmode, FFS mode, or the like can be used as the lateral electric field.

<Arrangement of Driving Electrodes and Detecting Electrodes>

As arrangement of driving electrodes and detecting electrodes in thetouch panel of the fourth embodiment, the arrangement of the drivingelectrodes and the detecting electrodes in either one of the firstembodiment and the first modification example to the fifth modificationexample thereof can be adopted. Further, as the arrangement of drivingelectrodes and detecting electrodes in the touch panel of the fourthembodiment, the arrangement of the driving electrodes and the detectingelectrodes in either one of the second embodiment and the firstmodification example to the sixth modification example thereof can beadopted.

Even in the touch panel used as a single body and the touch panelprovided in the display device of an on-cell type, there is such a casethat the width of a driving electrode becomes smaller than those of theother driving electrodes due to constraint of arrangement or the like.

In the fourth embodiment, however, the arrangement of the drivingelectrodes and the detecting electrodes shown in either one of the firstembodiment and the first modification example to the fifth modificationexample thereof can be adopted. Therefore, as explained with referenceto FIG. 7 or the like, even when the width WD2 of the driving electrodeTx1 and the width WD3 of the driving electrode Tx10 are smaller than therespective widths WD1 of the driving electrodes Tx2 to Tx9, theelectrostatic capacitance between each of the driving electrodes Tx1 andTx10 and the detecting electrode Rx can be increased. Therefore, theelectrostatic capacitance between each of the driving electrodes Tx1 andTx10 and the detecting electrode Rx can be prevented or inhibited frombecoming smaller than the electrostatic capacitance between each of thedriving electrodes Tx2 to Tx9 and the detecting electrode Rx.

Further, in the fourth embodiment, the arrangement of the drivingelectrodes and the detecting electrodes shown in either one of thesecond embodiment and the first modification example to the sixthmodification example thereof can be adopted. Therefore, as explainedwith reference to FIG. 16 or the like, even when the width WD2 of thedriving electrode Tx1 and the width WD3 of the driving electrode Tx10are smaller than the respective widths WD1 of the driving electrodes Tx2to Tx9, the electrostatic capacitance between each of the drivingelectrodes Tx1 and Tx10 and the detecting electrode Rx can be increased.Therefore, the electrostatic capacitance between each of the drivingelectrodes Tx1 and Tx10 and the detecting electrode Rx can be preventedor inhibited from becoming smaller than the electrostatic capacitancebetween each of the driving electrodes Tx2 to Tx9 and the detectingelectrode Rx.

Further, as the arrangement of driving electrodes and detectingelectrodes in the touch panel of the fourth embodiment, the arrangementof the driving electrodes and the detecting electrodes in either one ofthe third embodiment and the first modification example to the sixthmodification example thereof can be adopted.

Even in the touch panel used as a single body and the touch panelprovided in the display device of an on-cell type, there is such a casethat the width of a driving electrode becomes larger than those of theother driving electrodes due to constraint of arrangement or the like.

In the fourth embodiment, however, the arrangement of the drivingelectrodes and the detecting electrodes in either one of the thirdembodiment and the first modification example to the sixth modificationexample thereof can be adopted. Therefore, as explained with referenceto FIG. 23 or the like, even when the width WD2 of the driving electrodeTx1 and the width WD3 of the driving electrode Tx10 are larger than therespective widths WD1 of the driving electrodes Tx2 to Tx9, theelectrostatic capacitance between the each of the driving electrodes Tx1and Tx10 and the detecting electrode Rx can be decreased. Therefore, theelectrostatic capacitance between each of the driving electrodes Tx1 andTx10 and the detecting electrode Rx can be prevented or inhibited frombecoming larger than the electrostatic capacitance between each of thedriving electrodes Tx2 to Tx9 and the detecting electrode Rx.

In the fourth embodiment, in the touch panel used as a single body orthe touch panel provided in the display device of an on-cell type,adjustment can be performed in this manner that the electrostaticcapacitance between the driving electrode different in width from theother driving electrodes and the detecting electrode approaches theelectrostatic capacitance between each of the other driving electrodesand the detecting electrode.

Therefore, the tolerance of the detected capacitance detected when adriving voltage has been applied to the driving electrode different inwidth from the other driving electrodes to the lower limit or the upperlimit of the ADC range can be prevented from becoming small, so that anoise immunity of the detected capacitance can be prevented or inhibitedfrom lowering. Therefore, in the same manner as the first embodiment tothe third embodiment, the position detection accuracy can be preventedor inhibited from lowering on the driving electrode different in widthfrom the other driving electrodes and the position detection sensitivitycan be prevented or inhibited from lowering thereon as compared with onthe other driving electrodes. Therefore, the position detectionperformance on the stand-alone touch panel or the touch panel providedin the display device of an on-cell type can be improved.

(Fifth Embodiment)

Next, with reference to FIG. 36 to FIG. 42, electric equipment as anapplication example of the display device explained in the firstembodiment to the fourth embodiment and the modification examplesthereof will be described. It is possible to apply the display deviceswith a touch detection function of the first embodiment to the fourthembodiment and the modification examples thereof or the like toelectronic device in any field such as television equipment, a digitalcamera, a notebook type personal computer, such a portable terminaldevice as a mobile phone, or a video camera. In other words, it ispossible to apply the display devices with a touch detection function ofthe first embodiment to the fourth embodiment and the modificationexamples thereof or the like to electronic device in any field ofdisplaying a video signal inputted from the outside or a video signalproduced internally as an image or a video image.

<Television Equipment>

FIG. 36 is a perspective view representing an appearance of televisionequipment as one example of the electronic device of the fifthembodiment. The television equipment has a video image displaying screensection 513 including a front panel 511 and a filter glass 512. Thevideo image displaying screen section 513 is composed of the displaydevice with a touch detection function of an in-cell type or the displaydevice with a touch detection function of an on-cell type which has beendescribed in the first embodiment to the fourth embodiment and themodification examples thereof.

<Digital Camera>

FIG. 37 is a perspective view representing an appearance of a digitalcamera as one example of the electronic device of the fifth embodiment.The digital camera has, for example, a display section 522, a menuswitch 523, and a shutter button 524. The display section 522 iscomposed of the display device with a touch detection function of anin-cell type or the display device with a touch detection function of anon-cell type which has been described in the first embodiment to thefourth embodiment and the modification examples thereof.

<Notebook Type Personal Computer>

FIG. 38 is a perspective view representing an appearance of a notebooktype personal computer as one example of the electronic device of thefifth embodiment. The notebook type personal computer has, for example,a main body 531, a keyboard 532 for input operation of a character orthe like, and display section 533 for displaying an image. The displaysection 533 is composed of the display device with a touch detectionfunction of an in-cell type or the display device with a touch detectionfunction of an on-cell type which has been described in the firstembodiment to the fourth embodiment and the modification examplesthereof.

<Video Camera>

FIG. 39 is a perspective view representing an appearance of a videocamera as one example of the electronic device of the fifth embodiment.The video camera has, for example, a main body portion 541, a lens forsubject shooting provided on a front surface of the main body portion541, a start/stop switch 543 used at a shooting time, and a displaysection 544. The display section 544 is composed of the display devicewith a touch detection function of an in-cell type or the display devicewith a touch detection function of an on-cell type which has beendescribed in the first embodiment to the fourth embodiment and themodification examples thereof.

<Mobile Phone>

FIG. 40 and FIG. 41 are front views representing an appearance of amobile phone as one example of the electronic device of the fifthembodiment. FIG. 41 shows a state where the mobile phone shown in FIG.40 has been folded. The mobile phone is constituted by connecting, forexample, an upper side casing 551 and a lower side casing 552 at aconnecting portion (hinge portion) 553, and has a display 554, asub-display 555, a picture light 556, and a camera 557. The display 554or the sub-display 555 is composed of the display device with a touchdetection function of one of the first embodiment to the fourthembodiment and the modification examples thereof, or the like.

<Smartphone>

FIG. 42 is a front view representing an appearance of a smartphone asone example of the electronic device of the fifth embodiment. Thesmartphone has, for example, a casing 561 and a touch screen 562. Thetouch screen 562 is composed of, for example, a touch panel serving asan input device and a liquid crystal panel serving as a display portion,and is constituted of the display device with a touch detection functionof an in-cell type or the display device with a touch detection functionof an on-cell type which has been described in the first embodiment tothe fourth embodiment and the modification examples thereof.

The touch panel of the touch screen 562 is composed of, for example, thetouch panel TP1 described with reference to FIG. 6, and it is providedon a surface of the liquid crystal panel composed of, for example, thedisplay device LCD1 described with reference to FIG. 6. When a user useshis/her finger or a touch pen to perform such a gesture operation as atouch operation or a drag operation to the touch panel, the touch panelof the touch screen 562 detects coordinates of a position correspondingto the gesture operation to output the same to a control section (notshown).

The liquid crystal panel of the touch screen 562 is composed of, forexample, the display device LCD1 described with reference to FIG. 6, asdescribed above. Further, though not illustrated in FIG. 42, the liquidcrystal panel of the touch screen 562 composed of the display deviceLCD1 has a driving section composed of, for example, the driving circuitDR2 described with reference to FIG. 6. The driving section composed ofthe driving circuit DR2 causes each of pixel electrodes arrangedcorresponding to each of a plurality of pixels disposed in a matrixfashion in the display device LCD1 described with reference to FIG. 6 toperform display by applying a voltage as an image signal to the pixelelectrodes at respective constant timings.

<Main Feature and Advantageous Effect of This Embodiment>

In the fifth embodiment, in the input devices provided in the displaydevices of the various electronic devices described above, adjustmentcan be performed such that the electrostatic capacitance between thedriving electrode different in width from the other driving electrodesand the detecting electrode approaches the electrostatic capacitancebetween each of the other driving electrodes and the detectingelectrode.

Therefore, the tolerance of the detected capacitance detected when adriving voltage has been applied to the driving electrode different inwidth from the other driving electrodes to the lower limit or the upperlimit of the ADC range is prevented from becoming small, so that a noiseimmunity of the detected capacitance can be prevented or inhibited fromlowering. Therefore, in the same manner as the first embodiment to thefourth embodiment and the modification examples thereof, the positiondetection accuracy can be prevented or inhibited from lowering on thedriving electrode different in width from the other driving electrodesas compared with on the other driving electrodes so that the positiondetection sensitivity can be prevented or inhibited from lowering.Therefore, performances of the various electronic device described abovecan be improved.

In the foregoing, the invention made by the inventors of the presentinvention has been concretely described based on the embodiments.However, it is needless to say that the present invention is not limitedto the foregoing embodiments and various modifications and alterationscan be made within the scope of the present invention.

The present invention is effectively applied to an input device, adisplay device and electronic device.

It should be understood that various changes and modifications to thepresently preferred embodiments described herein will be apparent tothose skilled in the art. Such changes and modifications can be madewithout departing from the spirit and scope of the present subjectmatter and without diminishing its intended advantages. It is thereforeintended that such changes and modifications be covered by the appendedclaims.

The invention is claimed as follows:
 1. An input device comprising: aplurality of first electrodes extending in a first direction,respectively, and arranged in a second direction intersecting with thefirst direction in a plan view; a second electrode arranged outside atleast one side of an arrangement of the plurality of first electrodesand extending in the first direction in a plan view; and a plurality ofthird electrodes extending in the second direction, respectively, andarranged in the first direction in a plan view, wherein an inputposition is detected based upon a first electrostatic capacitancebetween the third electrode and the first electrode and a secondelectrostatic capacitance between the third electrode and the secondelectrode, wherein an area of a portion of the third electrodeoverlapping with the second electrode is smaller than an area of aportion of the third electrode overlapping with the first electrode,wherein a first width of the second electrode in the second direction issmaller than a second width of the first electrode in the seconddirection, and wherein the third electrode includes a first expandingportion for expanding the area of the third electrode on an oppositeside of the plurality of first electrodes interposing the secondelectrode in a plan view.
 2. The input device according to claim 1,wherein the first expanding portion expands the area of the thirdelectrode such that the first electrostatic capacitance is equal to thesecond electrostatic capacitance.
 3. The input device according to claim1, wherein the first expanding portion is in contact with the secondelectrode in a plan view.
 4. The input device according to claim 1,wherein the third electrode includes a main body portion extending inthe second direction in a plan view, and the expanding portion is anoverhang portion projecting in the first direction from the main bodyportion, on an opposite side of the plurality of first electrodesinterposing the second electrode in a plan view.
 5. The input deviceaccording to claim 1, further comprising a fourth electrode arrangedoutside the other side of the arrangement of the plurality of firstelectrodes and extending in the first direction, wherein the inputposition is detected based upon the first electrostatic capacitance, thesecond electrostatic capacitance, and an electrostatic capacitancebetween the third electrode and the fourth electrode, a third width ofthe fourth electrode in the second direction is smaller than the secondwidth, and the third electrode includes a second expanding portion forexpanding the area of the third electrode, on a side opposite of theplurality of first electrodes interposing the fourth electrode in a planview.
 6. The input device according to claim 1, wherein the firstexpanding portion does not face either of the first electrode and thesecond electrode.